Merge pull request #1224 from 0xProject/feature/contracts/multiAssetProxy

Implement MultiAssetProxy

13 files changed, 1510 insertions, 221 deletions

diff --git a/packages/contracts/CHANGELOG.json b/packages/contracts/CHANGELOG.json
index 00f94c83b..7dfa06990 100644
--- a/packages/contracts/CHANGELOG.json
+++ b/packages/contracts/CHANGELOG.json
@@ -1,5 +1,15 @@
 [
     {
+        "name": "MultiAssetProxy",
+        "version": "1.0.0",
+        "changes": [
+            {
+                "note": "Add MultiAssetProxy implementation",
+                "pr": 1224
+            }
+        ]
+    },
+    {
         "name": "OrderValidator",
         "version": "1.0.1",
         "changes": [
diff --git a/packages/contracts/compiler.json b/packages/contracts/compiler.json
index af3980b4e..c824e4645 100644
--- a/packages/contracts/compiler.json
+++ b/packages/contracts/compiler.json
@@ -38,6 +38,7 @@
         "IValidator",
         "IWallet",
         "MixinAuthorizable",
+        "MultiAssetProxy",
         "MultiSigWallet",
         "MultiSigWalletWithTimeLock",
         "OrderValidator",
diff --git a/packages/contracts/contracts/protocol/AssetProxy/MultiAssetProxy.sol b/packages/contracts/contracts/protocol/AssetProxy/MultiAssetProxy.sol
new file mode 100644
index 000000000..42231e73b
--- /dev/null
+++ b/packages/contracts/contracts/protocol/AssetProxy/MultiAssetProxy.sol
@@ -0,0 +1,300 @@
+/*
+
+  Copyright 2018 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity 0.4.24;
+
+import "../Exchange/MixinAssetProxyDispatcher.sol";
+import "./MixinAuthorizable.sol";
+
+
+contract MultiAssetProxy is
+    MixinAssetProxyDispatcher,
+    MixinAuthorizable
+{
+    // Id of this proxy.
+    bytes4 constant internal PROXY_ID = bytes4(keccak256("MultiAsset(uint256[],bytes[])"));
+
+    // solhint-disable-next-line payable-fallback
+    function ()
+        external
+    {
+        assembly {
+            // The first 4 bytes of calldata holds the function selector
+            let selector := and(calldataload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
+
+            // `transferFrom` will be called with the following parameters:
+            // assetData Encoded byte array.
+            // from Address to transfer asset from.
+            // to Address to transfer asset to.
+            // amount Amount of asset to transfer.
+            // bytes4(keccak256("transferFrom(bytes,address,address,uint256)")) = 0xa85e59e4
+            if eq(selector, 0xa85e59e400000000000000000000000000000000000000000000000000000000) {
+
+                // To lookup a value in a mapping, we load from the storage location keccak256(k, p),
+                // where k is the key left padded to 32 bytes and p is the storage slot
+                mstore(0, caller)
+                mstore(32, authorized_slot)
+
+                // Revert if authorized[msg.sender] == false
+                if iszero(sload(keccak256(0, 64))) {
+                    // Revert with `Error("SENDER_NOT_AUTHORIZED")`
+                    mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
+                    mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
+                    mstore(64, 0x0000001553454e4445525f4e4f545f415554484f52495a454400000000000000)
+                    mstore(96, 0)
+                    revert(0, 100)
+                }
+
+                // `transferFrom`.
+                // The function is marked `external`, so no abi decoding is done for
+                // us. Instead, we expect the `calldata` memory to contain the
+                // following:
+                //
+                // | Area     | Offset | Length  | Contents                            |
+                // |----------|--------|---------|-------------------------------------|
+                // | Header   | 0      | 4       | function selector                   |
+                // | Params   |        | 4 * 32  | function parameters:                |
+                // |          | 4      |         |   1. offset to assetData (*)        |
+                // |          | 36     |         |   2. from                           |
+                // |          | 68     |         |   3. to                             |
+                // |          | 100    |         |   4. amount                         |
+                // | Data     |        |         | assetData:                          |
+                // |          | 132    | 32      | assetData Length                    |
+                // |          | 164    | **      | assetData Contents                  |
+                //
+                // (*): offset is computed from start of function parameters, so offset
+                //      by an additional 4 bytes in the calldata.
+                //
+                // (**): see table below to compute length of assetData Contents
+                //
+                // WARNING: The ABIv2 specification allows additional padding between
+                //          the Params and Data section. This will result in a larger
+                //          offset to assetData.
+
+                // Load offset to `assetData`
+                let assetDataOffset := calldataload(4)
+
+                // Asset data itself is encoded as follows:
+                //
+                // | Area     | Offset      | Length  | Contents                            |
+                // |----------|-------------|---------|-------------------------------------|
+                // | Header   | 0           | 4       | assetProxyId                        |
+                // | Params   |             | 2 * 32  | function parameters:                |
+                // |          | 4           |         |   1. offset to amounts (*)          |
+                // |          | 36          |         |   2. offset to nestedAssetData (*)  |
+                // | Data     |             |         | amounts:                            |
+                // |          | 68          | 32      | amounts Length                      |
+                // |          | 100         | a       | amounts Contents                    | 
+                // |          |             |         | nestedAssetData:                    |
+                // |          | 100 + a     | 32      | nestedAssetData Length              |
+                // |          | 132 + a     | b       | nestedAssetData Contents (offsets)  |
+                // |          | 132 + a + b |         | nestedAssetData[0, ..., len]        |
+
+                // In order to find the offset to `amounts`, we must add:
+                // 4 (function selector)
+                // + assetDataOffset
+                // + 32 (assetData len)
+                // + 4 (assetProxyId)
+                let amountsOffset := calldataload(add(assetDataOffset, 40))
+
+                // In order to find the offset to `nestedAssetData`, we must add:
+                // 4 (function selector)
+                // + assetDataOffset
+                // + 32 (assetData len)
+                // + 4 (assetProxyId)
+                // + 32 (amounts offset)
+                let nestedAssetDataOffset := calldataload(add(assetDataOffset, 72))
+
+                // In order to find the start of the `amounts` contents, we must add: 
+                // 4 (function selector) 
+                // + assetDataOffset 
+                // + 32 (assetData len)
+                // + 4 (assetProxyId)
+                // + amountsOffset
+                // + 32 (amounts len)
+                let amountsContentsStart := add(assetDataOffset, add(amountsOffset, 72))
+
+                // Load number of elements in `amounts`
+                let amountsLen := calldataload(sub(amountsContentsStart, 32))
+
+                // In order to find the start of the `nestedAssetData` contents, we must add: 
+                // 4 (function selector) 
+                // + assetDataOffset 
+                // + 32 (assetData len)
+                // + 4 (assetProxyId)
+                // + nestedAssetDataOffset
+                // + 32 (nestedAssetData len)
+                let nestedAssetDataContentsStart := add(assetDataOffset, add(nestedAssetDataOffset, 72))
+
+                // Load number of elements in `nestedAssetData`
+                let nestedAssetDataLen := calldataload(sub(nestedAssetDataContentsStart, 32))
+
+                // Revert if number of elements in `amounts` differs from number of elements in `nestedAssetData`
+                if iszero(eq(amountsLen, nestedAssetDataLen)) {
+                    // Revert with `Error("LENGTH_MISMATCH")`
+                    mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
+                    mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
+                    mstore(64, 0x0000000f4c454e4754485f4d49534d4154434800000000000000000000000000)
+                    mstore(96, 0)
+                    revert(0, 100)
+                }
+
+                // Copy `transferFrom` selector, offset to `assetData`, `from`, and `to` from calldata to memory
+                calldatacopy(
+                    0,   // memory can safely be overwritten from beginning
+                    0,   // start of calldata
+                    100  // length of selector (4) and 3 params (32 * 3)
+                )
+
+                // Overwrite existing offset to `assetData` with our own
+                mstore(4, 128)
+                
+                // Load `amount`
+                let amount := calldataload(100)
+        
+                // Calculate number of bytes in `amounts` contents
+                let amountsByteLen := mul(amountsLen, 32)
+
+                // Initialize `assetProxyId` and `assetProxy` to 0
+                let assetProxyId := 0
+                let assetProxy := 0
+
+                // Loop through `amounts` and `nestedAssetData`, calling `transferFrom` for each respective element
+                for {let i := 0} lt(i, amountsByteLen) {i := add(i, 32)} {
+
+                    // Calculate the total amount
+                    let amountsElement := calldataload(add(amountsContentsStart, i))
+                    let totalAmount := mul(amountsElement, amount)
+
+                    // Revert if multiplication resulted in an overflow
+                    if iszero(eq(div(totalAmount, amount), amountsElement)) {
+                        // Revert with `Error("UINT256_OVERFLOW")`
+                        mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
+                        mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
+                        mstore(64, 0x0000001055494e543235365f4f564552464c4f57000000000000000000000000)
+                        mstore(96, 0)
+                        revert(0, 100)
+                    }
+
+                    // Write `totalAmount` to memory
+                    mstore(100, totalAmount)
+
+                    // Load offset to `nestedAssetData[i]`
+                    let nestedAssetDataElementOffset := calldataload(add(nestedAssetDataContentsStart, i))
+
+                    // In order to find the start of the `nestedAssetData[i]` contents, we must add:
+                    // 4 (function selector) 
+                    // + assetDataOffset 
+                    // + 32 (assetData len)
+                    // + 4 (assetProxyId)
+                    // + nestedAssetDataOffset
+                    // + 32 (nestedAssetData len)
+                    // + nestedAssetDataElementOffset
+                    // + 32 (nestedAssetDataElement len)
+                    let nestedAssetDataElementContentsStart := add(assetDataOffset, add(nestedAssetDataOffset, add(nestedAssetDataElementOffset, 104)))
+
+                    // Load length of `nestedAssetData[i]`
+                    let nestedAssetDataElementLenStart := sub(nestedAssetDataElementContentsStart, 32)
+                    let nestedAssetDataElementLen := calldataload(nestedAssetDataElementLenStart)
+
+                    // Revert if the `nestedAssetData` does not contain a 4 byte `assetProxyId`
+                    if lt(nestedAssetDataElementLen, 4) {
+                        // Revert with `Error("LENGTH_GREATER_THAN_3_REQUIRED")`
+                        mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
+                        mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
+                        mstore(64, 0x0000001e4c454e4754485f475245415445525f5448414e5f335f524551554952)
+                        mstore(96, 0x4544000000000000000000000000000000000000000000000000000000000000)
+                        revert(0, 100)
+                    }
+
+                    // Load AssetProxy id
+                    let currentAssetProxyId := and(
+                        calldataload(nestedAssetDataElementContentsStart),
+                        0xffffffff00000000000000000000000000000000000000000000000000000000
+                    )
+
+                    // Only load `assetProxy` if `currentAssetProxyId` does not equal `assetProxyId`
+                    // We do not need to check if `currentAssetProxyId` is 0 since `assetProxy` is also initialized to 0
+                    if iszero(eq(currentAssetProxyId, assetProxyId)) {
+                        // Update `assetProxyId`
+                        assetProxyId := currentAssetProxyId
+                        // To lookup a value in a mapping, we load from the storage location keccak256(k, p),
+                        // where k is the key left padded to 32 bytes and p is the storage slot
+                        mstore(132, assetProxyId)
+                        mstore(164, assetProxies_slot)
+                        assetProxy := sload(keccak256(132, 64))
+                    }
+                    
+                    // Revert if AssetProxy with given id does not exist
+                    if iszero(assetProxy) {
+                        // Revert with `Error("ASSET_PROXY_DOES_NOT_EXIST")`
+                        mstore(0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
+                        mstore(32, 0x0000002000000000000000000000000000000000000000000000000000000000)
+                        mstore(64, 0x0000001a41535345545f50524f58595f444f45535f4e4f545f45584953540000)
+                        mstore(96, 0)
+                        revert(0, 100)
+                    }
+    
+                    // Copy `nestedAssetData[i]` from calldata to memory
+                    calldatacopy(
+                        132,                                // memory slot after `amounts[i]`
+                        nestedAssetDataElementLenStart,     // location of `nestedAssetData[i]` in calldata
+                        add(nestedAssetDataElementLen, 32)  // `nestedAssetData[i].length` plus 32 byte length
+                    )
+
+                    // call `assetProxy.transferFrom`
+                    let success := call(
+                        gas,                                    // forward all gas
+                        assetProxy,                             // call address of asset proxy
+                        0,                                      // don't send any ETH
+                        0,                                      // pointer to start of input
+                        add(164, nestedAssetDataElementLen),    // length of input  
+                        0,                                      // write output over memory that won't be reused
+                        0                                       // don't copy output to memory
+                    )
+
+                    // Revert with reason given by AssetProxy if `transferFrom` call failed
+                    if iszero(success) {
+                        returndatacopy(
+                            0,                // copy to memory at 0
+                            0,                // copy from return data at 0
+                            returndatasize()  // copy all return data
+                        )
+                        revert(0, returndatasize())
+                    }
+                }
+
+                // Return if no `transferFrom` calls reverted
+                return(0, 0)
+            }
+
+            // Revert if undefined function is called
+            revert(0, 0)
+        }
+    }
+
+    /// @dev Gets the proxy id associated with the proxy address.
+    /// @return Proxy id.
+    function getProxyId()
+        external
+        pure
+        returns (bytes4)
+    {
+        return PROXY_ID;
+    }
+}
diff --git a/packages/contracts/contracts/protocol/AssetProxy/interfaces/IAssetData.sol b/packages/contracts/contracts/protocol/AssetProxy/interfaces/IAssetData.sol
index 3e76e38dd..e2da68919 100644
--- a/packages/contracts/contracts/protocol/AssetProxy/interfaces/IAssetData.sol
+++ b/packages/contracts/contracts/protocol/AssetProxy/interfaces/IAssetData.sol
@@ -18,6 +18,7 @@
 
 // solhint-disable
 pragma solidity 0.4.24;
+pragma experimental ABIEncoderV2;
 
 
 // @dev Interface of the asset proxy's assetData.
@@ -26,15 +27,18 @@ pragma solidity 0.4.24;
 interface IAssetData {
 
     function ERC20Token(address tokenContract)
-        external
-        pure;
+        external;
     
     function ERC721Token(
         address tokenContract,
-        uint256 tokenId,
-        bytes receiverData
+        uint256 tokenId
     )
-        external
-        pure;
+        external;
+
+    function MultiAsset(
+        uint256[] amounts,
+        bytes[] nestedAssetData
+    )
+        external;
     
 }
diff --git a/packages/contracts/package.json b/packages/contracts/package.json
index 6f031fcee..16dd3c9c1 100644
--- a/packages/contracts/package.json
+++ b/packages/contracts/package.json
@@ -19,7 +19,8 @@
         "test:coverage": "SOLIDITY_COVERAGE=true run-s build run_mocha coverage:report:text coverage:report:lcov",
         "test:profiler": "SOLIDITY_PROFILER=true run-s build run_mocha profiler:report:html",
         "test:trace": "SOLIDITY_REVERT_TRACE=true run-s build run_mocha",
-        "run_mocha": "mocha --require source-map-support/register --require make-promises-safe 'lib/test/**/*.js' --timeout 100000 --bail --exit",
+        "run_mocha":
+            "mocha --require source-map-support/register --require make-promises-safe 'lib/test/**/*.js' --timeout 100000 --bail --exit",
         "compile": "sol-compiler --contracts-dir contracts",
         "clean": "shx rm -rf lib generated-artifacts generated-wrappers",
         "generate_contract_wrappers": "abi-gen --abis  ${npm_package_config_abis} --template ../../node_modules/@0x/abi-gen-templates/contract.handlebars --partials '../../node_modules/@0x/abi-gen-templates/partials/**/*.handlebars' --output generated-wrappers --backend ethers",
@@ -32,7 +33,8 @@
         "lint-contracts": "solhint contracts/**/**/**/**/*.sol"
     },
     "config": {
-        "abis": "generated-artifacts/@(AssetProxyOwner|DummyERC20Token|DummyERC721Receiver|DummyERC721Token|DummyMultipleReturnERC20Token|DummyNoReturnERC20Token|ERC20Token|ERC20Proxy|ERC721Token|ERC721Proxy|Forwarder|Exchange|ExchangeWrapper|IAssetData|IAssetProxy|InvalidERC721Receiver|MixinAuthorizable|MultiSigWallet|MultiSigWalletWithTimeLock|OrderValidator|ReentrantERC20Token|TestAssetProxyOwner|TestAssetProxyDispatcher|TestConstants|TestExchangeInternals|TestLibBytes|TestLibs|TestSignatureValidator|TestStaticCallReceiver|Validator|Wallet|Whitelist|WETH9|ZRXToken).json"
+        "abis":
+            "generated-artifacts/@(AssetProxyOwner|DummyERC20Token|DummyERC721Receiver|DummyERC721Token|DummyMultipleReturnERC20Token|DummyNoReturnERC20Token|ERC20Token|ERC20Proxy|ERC721Token|ERC721Proxy|Forwarder|Exchange|ExchangeWrapper|IAssetData|IAssetProxy|InvalidERC721Receiver|MixinAuthorizable|MultiAssetProxy|MultiSigWallet|MultiSigWalletWithTimeLock|OrderValidator|ReentrantERC20Token|TestAssetProxyOwner|TestAssetProxyDispatcher|TestConstants|TestExchangeInternals|TestLibBytes|TestLibs|TestSignatureValidator|TestStaticCallReceiver|Validator|Wallet|Whitelist|WETH9|ZRXToken).json"
     },
     "repository": {
         "type": "git",
diff --git a/packages/contracts/src/artifacts/index.ts b/packages/contracts/src/artifacts/index.ts
index c30972a91..97c1b6209 100644
--- a/packages/contracts/src/artifacts/index.ts
+++ b/packages/contracts/src/artifacts/index.ts
@@ -19,6 +19,7 @@ import * as InvalidERC721Receiver from '../../generated-artifacts/InvalidERC721R
 import * as IValidator from '../../generated-artifacts/IValidator.json';
 import * as IWallet from '../../generated-artifacts/IWallet.json';
 import * as MixinAuthorizable from '../../generated-artifacts/MixinAuthorizable.json';
+import * as MultiAssetProxy from '../../generated-artifacts/MultiAssetProxy.json';
 import * as MultiSigWallet from '../../generated-artifacts/MultiSigWallet.json';
 import * as MultiSigWalletWithTimeLock from '../../generated-artifacts/MultiSigWalletWithTimeLock.json';
 import * as OrderValidator from '../../generated-artifacts/OrderValidator.json';
@@ -57,6 +58,7 @@ export const artifacts = {
     IWallet: IWallet as ContractArtifact,
     InvalidERC721Receiver: InvalidERC721Receiver as ContractArtifact,
     MixinAuthorizable: MixinAuthorizable as ContractArtifact,
+    MultiAssetProxy: MultiAssetProxy as ContractArtifact,
     MultiSigWallet: MultiSigWallet as ContractArtifact,
     MultiSigWalletWithTimeLock: MultiSigWalletWithTimeLock as ContractArtifact,
     OrderValidator: OrderValidator as ContractArtifact,
diff --git a/packages/contracts/test/asset_proxy/proxies.ts b/packages/contracts/test/asset_proxy/proxies.ts
index b8305993e..8fa1e602a 100644
--- a/packages/contracts/test/asset_proxy/proxies.ts
+++ b/packages/contracts/test/asset_proxy/proxies.ts
@@ -12,7 +12,9 @@ import { DummyMultipleReturnERC20TokenContract } from '../../generated-wrappers/
 import { DummyNoReturnERC20TokenContract } from '../../generated-wrappers/dummy_no_return_erc20_token';
 import { ERC20ProxyContract } from '../../generated-wrappers/erc20_proxy';
 import { ERC721ProxyContract } from '../../generated-wrappers/erc721_proxy';
+import { IAssetDataContract } from '../../generated-wrappers/i_asset_data';
 import { IAssetProxyContract } from '../../generated-wrappers/i_asset_proxy';
+import { MultiAssetProxyContract } from '../../generated-wrappers/multi_asset_proxy';
 import { artifacts } from '../../src/artifacts';
 import { expectTransactionFailedAsync, expectTransactionFailedWithoutReasonAsync } from '../utils/assertions';
 import { chaiSetup } from '../utils/chai_setup';
@@ -30,26 +32,35 @@ const assetProxyInterface = new IAssetProxyContract(
     constants.NULL_ADDRESS,
     provider,
 );
+const assetDataInterface = new IAssetDataContract(
+    artifacts.IAssetData.compilerOutput.abi,
+    constants.NULL_ADDRESS,
+    provider,
+);
 
 // tslint:disable:no-unnecessary-type-assertion
 describe('Asset Transfer Proxies', () => {
     let owner: string;
     let notAuthorized: string;
-    let exchangeAddress: string;
-    let makerAddress: string;
-    let takerAddress: string;
+    let authorized: string;
+    let fromAddress: string;
+    let toAddress: string;
 
-    let zrxToken: DummyERC20TokenContract;
-    let erc721Token: DummyERC721TokenContract;
+    let erc20TokenA: DummyERC20TokenContract;
+    let erc20TokenB: DummyERC20TokenContract;
+    let erc721TokenA: DummyERC721TokenContract;
+    let erc721TokenB: DummyERC721TokenContract;
     let erc721Receiver: DummyERC721ReceiverContract;
     let erc20Proxy: ERC20ProxyContract;
     let erc721Proxy: ERC721ProxyContract;
     let noReturnErc20Token: DummyNoReturnERC20TokenContract;
     let multipleReturnErc20Token: DummyMultipleReturnERC20TokenContract;
+    let multiAssetProxy: MultiAssetProxyContract;
 
     let erc20Wrapper: ERC20Wrapper;
     let erc721Wrapper: ERC721Wrapper;
-    let erc721MakerTokenId: BigNumber;
+    let erc721AFromTokenId: BigNumber;
+    let erc721BFromTokenId: BigNumber;
 
     before(async () => {
         await blockchainLifecycle.startAsync();
@@ -59,41 +70,73 @@ describe('Asset Transfer Proxies', () => {
     });
     before(async () => {
         const accounts = await web3Wrapper.getAvailableAddressesAsync();
-        const usedAddresses = ([owner, notAuthorized, exchangeAddress, makerAddress, takerAddress] = _.slice(
-            accounts,
-            0,
-            5,
-        ));
+        const usedAddresses = ([owner, notAuthorized, authorized, fromAddress, toAddress] = _.slice(accounts, 0, 5));
 
         erc20Wrapper = new ERC20Wrapper(provider, usedAddresses, owner);
         erc721Wrapper = new ERC721Wrapper(provider, usedAddresses, owner);
 
-        const numDummyErc20ToDeploy = 1;
-        [zrxToken] = await erc20Wrapper.deployDummyTokensAsync(numDummyErc20ToDeploy, constants.DUMMY_TOKEN_DECIMALS);
+        // Deploy AssetProxies
         erc20Proxy = await erc20Wrapper.deployProxyAsync();
-        await erc20Wrapper.setBalancesAndAllowancesAsync();
+        erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        multiAssetProxy = await MultiAssetProxyContract.deployFrom0xArtifactAsync(
+            artifacts.MultiAssetProxy,
+            provider,
+            txDefaults,
+        );
+
+        // Configure ERC20Proxy
         await web3Wrapper.awaitTransactionSuccessAsync(
-            await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeAddress, {
+            await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(authorized, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(multiAssetProxy.address, {
                 from: owner,
             }),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
 
-        [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
-        erc721Proxy = await erc721Wrapper.deployProxyAsync();
-        await erc721Wrapper.setBalancesAndAllowancesAsync();
-        const erc721Balances = await erc721Wrapper.getBalancesAsync();
-        erc721MakerTokenId = erc721Balances[makerAddress][erc721Token.address][0];
+        // Configure ERC721Proxy
         await web3Wrapper.awaitTransactionSuccessAsync(
-            await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeAddress, {
+            await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(authorized, {
                 from: owner,
             }),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
-        erc721Receiver = await DummyERC721ReceiverContract.deployFrom0xArtifactAsync(
-            artifacts.DummyERC721Receiver,
-            provider,
-            txDefaults,
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(multiAssetProxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+
+        // Configure MultiAssetProxy
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.addAuthorizedAddress.sendTransactionAsync(authorized, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.registerAssetProxy.sendTransactionAsync(erc721Proxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+
+        // Deploy and configure ERC20 tokens
+        const numDummyErc20ToDeploy = 2;
+        [erc20TokenA, erc20TokenB] = await erc20Wrapper.deployDummyTokensAsync(
+            numDummyErc20ToDeploy,
+            constants.DUMMY_TOKEN_DECIMALS,
         );
         noReturnErc20Token = await DummyNoReturnERC20TokenContract.deployFrom0xArtifactAsync(
             artifacts.DummyNoReturnERC20Token,
@@ -104,30 +147,32 @@ describe('Asset Transfer Proxies', () => {
             constants.DUMMY_TOKEN_DECIMALS,
             constants.DUMMY_TOKEN_TOTAL_SUPPLY,
         );
+        multipleReturnErc20Token = await DummyMultipleReturnERC20TokenContract.deployFrom0xArtifactAsync(
+            artifacts.DummyMultipleReturnERC20Token,
+            provider,
+            txDefaults,
+            constants.DUMMY_TOKEN_NAME,
+            constants.DUMMY_TOKEN_SYMBOL,
+            constants.DUMMY_TOKEN_DECIMALS,
+            constants.DUMMY_TOKEN_TOTAL_SUPPLY,
+        );
+
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
         await web3Wrapper.awaitTransactionSuccessAsync(
-            await noReturnErc20Token.setBalance.sendTransactionAsync(makerAddress, constants.INITIAL_ERC20_BALANCE),
+            await noReturnErc20Token.setBalance.sendTransactionAsync(fromAddress, constants.INITIAL_ERC20_BALANCE),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
         await web3Wrapper.awaitTransactionSuccessAsync(
             await noReturnErc20Token.approve.sendTransactionAsync(
                 erc20Proxy.address,
                 constants.INITIAL_ERC20_ALLOWANCE,
-                { from: makerAddress },
+                { from: fromAddress },
             ),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
-        multipleReturnErc20Token = await DummyMultipleReturnERC20TokenContract.deployFrom0xArtifactAsync(
-            artifacts.DummyMultipleReturnERC20Token,
-            provider,
-            txDefaults,
-            constants.DUMMY_TOKEN_NAME,
-            constants.DUMMY_TOKEN_SYMBOL,
-            constants.DUMMY_TOKEN_DECIMALS,
-            constants.DUMMY_TOKEN_TOTAL_SUPPLY,
-        );
         await web3Wrapper.awaitTransactionSuccessAsync(
             await multipleReturnErc20Token.setBalance.sendTransactionAsync(
-                makerAddress,
+                fromAddress,
                 constants.INITIAL_ERC20_BALANCE,
             ),
             constants.AWAIT_TRANSACTION_MINED_MS,
@@ -136,10 +181,23 @@ describe('Asset Transfer Proxies', () => {
             await multipleReturnErc20Token.approve.sendTransactionAsync(
                 erc20Proxy.address,
                 constants.INITIAL_ERC20_ALLOWANCE,
-                { from: makerAddress },
+                { from: fromAddress },
             ),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
+
+        // Deploy and configure ERC721 tokens and receiver
+        [erc721TokenA, erc721TokenB] = await erc721Wrapper.deployDummyTokensAsync();
+        erc721Receiver = await DummyERC721ReceiverContract.deployFrom0xArtifactAsync(
+            artifacts.DummyERC721Receiver,
+            provider,
+            txDefaults,
+        );
+
+        await erc721Wrapper.setBalancesAndAllowancesAsync();
+        const erc721Balances = await erc721Wrapper.getBalancesAsync();
+        erc721AFromTokenId = erc721Balances[fromAddress][erc721TokenA.address][0];
+        erc721BFromTokenId = erc721Balances[fromAddress][erc721TokenB.address][0];
     });
     beforeEach(async () => {
         await blockchainLifecycle.startAsync();
@@ -147,7 +205,8 @@ describe('Asset Transfer Proxies', () => {
     afterEach(async () => {
         await blockchainLifecycle.revertAsync();
     });
-    describe('Transfer Proxy - ERC20', () => {
+
+    describe('ERC20Proxy', () => {
         it('should revert if undefined function is called', async () => {
             const undefinedSelector = '0x01020304';
             await expectTransactionFailedWithoutReasonAsync(
@@ -159,141 +218,146 @@ describe('Asset Transfer Proxies', () => {
                 }),
             );
         });
+        it('should have an id of 0xf47261b0', async () => {
+            const proxyId = await erc20Proxy.getProxyId.callAsync();
+            const expectedProxyId = '0xf47261b0';
+            expect(proxyId).to.equal(expectedProxyId);
+        });
         describe('transferFrom', () => {
             it('should successfully transfer tokens', async () => {
                 // Construct ERC20 asset data
-                const encodedAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
-                // Perform a transfer from makerAddress to takerAddress
+                const encodedAssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                // Perform a transfer from fromAddress to toAddress
                 const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
                 const newBalances = await erc20Wrapper.getBalancesAsync();
-                expect(newBalances[makerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[makerAddress][zrxToken.address].minus(amount),
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(amount),
                 );
-                expect(newBalances[takerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[takerAddress][zrxToken.address].add(amount),
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(amount),
                 );
             });
 
             it('should successfully transfer tokens that do not return a value', async () => {
                 // Construct ERC20 asset data
                 const encodedAssetData = assetDataUtils.encodeERC20AssetData(noReturnErc20Token.address);
-                // Perform a transfer from makerAddress to takerAddress
-                const initialMakerBalance = await noReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const initialTakerBalance = await noReturnErc20Token.balanceOf.callAsync(takerAddress);
+                // Perform a transfer from fromAddress to toAddress
+                const initialFromBalance = await noReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const initialToBalance = await noReturnErc20Token.balanceOf.callAsync(toAddress);
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
-                const newMakerBalance = await noReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const newTakerBalance = await noReturnErc20Token.balanceOf.callAsync(takerAddress);
-                expect(newMakerBalance).to.be.bignumber.equal(initialMakerBalance.minus(amount));
-                expect(newTakerBalance).to.be.bignumber.equal(initialTakerBalance.plus(amount));
+                const newFromBalance = await noReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const newToBalance = await noReturnErc20Token.balanceOf.callAsync(toAddress);
+                expect(newFromBalance).to.be.bignumber.equal(initialFromBalance.minus(amount));
+                expect(newToBalance).to.be.bignumber.equal(initialToBalance.plus(amount));
             });
 
             it('should successfully transfer tokens and ignore extra assetData', async () => {
                 // Construct ERC20 asset data
                 const extraData = '0102030405060708';
-                const encodedAssetData = `${assetDataUtils.encodeERC20AssetData(zrxToken.address)}${extraData}`;
-                // Perform a transfer from makerAddress to takerAddress
+                const encodedAssetData = `${assetDataUtils.encodeERC20AssetData(erc20TokenA.address)}${extraData}`;
+                // Perform a transfer from fromAddress to toAddress
                 const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
                 const newBalances = await erc20Wrapper.getBalancesAsync();
-                expect(newBalances[makerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[makerAddress][zrxToken.address].minus(amount),
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(amount),
                 );
-                expect(newBalances[takerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[takerAddress][zrxToken.address].add(amount),
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(amount),
                 );
             });
 
             it('should do nothing if transferring 0 amount of a token', async () => {
                 // Construct ERC20 asset data
-                const encodedAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
-                // Perform a transfer from makerAddress to takerAddress
+                const encodedAssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                // Perform a transfer from fromAddress to toAddress
                 const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(0);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
                 const newBalances = await erc20Wrapper.getBalancesAsync();
-                expect(newBalances[makerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[makerAddress][zrxToken.address],
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address],
                 );
-                expect(newBalances[takerAddress][zrxToken.address]).to.be.bignumber.equal(
-                    erc20Balances[takerAddress][zrxToken.address],
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address],
                 );
             });
 
-            it('should throw if allowances are too low', async () => {
+            it('should revert if allowances are too low', async () => {
                 // Construct ERC20 asset data
-                const encodedAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
+                const encodedAssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
                 // Create allowance less than transfer amount. Set allowance on proxy.
                 const allowance = new BigNumber(0);
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
-                    await zrxToken.approve.sendTransactionAsync(erc20Proxy.address, allowance, {
-                        from: makerAddress,
+                    await erc20TokenA.approve.sendTransactionAsync(erc20Proxy.address, allowance, {
+                        from: fromAddress,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
@@ -303,7 +367,7 @@ describe('Asset Transfer Proxies', () => {
                     web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.TransferFailed,
                 );
@@ -311,7 +375,7 @@ describe('Asset Transfer Proxies', () => {
                 expect(newBalances).to.deep.equal(erc20Balances);
             });
 
-            it('should throw if allowances are too low and token does not return a value', async () => {
+            it('should revert if allowances are too low and token does not return a value', async () => {
                 // Construct ERC20 asset data
                 const encodedAssetData = assetDataUtils.encodeERC20AssetData(noReturnErc20Token.address);
                 // Create allowance less than transfer amount. Set allowance on proxy.
@@ -319,42 +383,42 @@ describe('Asset Transfer Proxies', () => {
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await noReturnErc20Token.approve.sendTransactionAsync(erc20Proxy.address, allowance, {
-                        from: makerAddress,
+                        from: fromAddress,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
-                const initialMakerBalance = await noReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const initialTakerBalance = await noReturnErc20Token.balanceOf.callAsync(takerAddress);
+                const initialFromBalance = await noReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const initialToBalance = await noReturnErc20Token.balanceOf.callAsync(toAddress);
                 // Perform a transfer; expect this to fail.
                 await expectTransactionFailedAsync(
                     web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.TransferFailed,
                 );
-                const newMakerBalance = await noReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const newTakerBalance = await noReturnErc20Token.balanceOf.callAsync(takerAddress);
-                expect(newMakerBalance).to.be.bignumber.equal(initialMakerBalance);
-                expect(newTakerBalance).to.be.bignumber.equal(initialTakerBalance);
+                const newFromBalance = await noReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const newToBalance = await noReturnErc20Token.balanceOf.callAsync(toAddress);
+                expect(newFromBalance).to.be.bignumber.equal(initialFromBalance);
+                expect(newToBalance).to.be.bignumber.equal(initialToBalance);
             });
 
-            it('should throw if requesting address is not authorized', async () => {
+            it('should revert if caller is not authorized', async () => {
                 // Construct ERC20 asset data
-                const encodedAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
-                // Perform a transfer from makerAddress to takerAddress
+                const encodedAssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 const erc20Balances = await erc20Wrapper.getBalancesAsync();
@@ -370,42 +434,36 @@ describe('Asset Transfer Proxies', () => {
                 expect(newBalances).to.deep.equal(erc20Balances);
             });
 
-            it('should throw if token returns more than 32 bytes', async () => {
+            it('should revert if token returns more than 32 bytes', async () => {
                 // Construct ERC20 asset data
                 const encodedAssetData = assetDataUtils.encodeERC20AssetData(multipleReturnErc20Token.address);
                 const amount = new BigNumber(10);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
-                const initialMakerBalance = await multipleReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const initialTakerBalance = await multipleReturnErc20Token.balanceOf.callAsync(takerAddress);
+                const initialFromBalance = await multipleReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const initialToBalance = await multipleReturnErc20Token.balanceOf.callAsync(toAddress);
                 // Perform a transfer; expect this to fail.
                 await expectTransactionFailedAsync(
                     web3Wrapper.sendTransactionAsync({
                         to: erc20Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.TransferFailed,
                 );
-                const newMakerBalance = await multipleReturnErc20Token.balanceOf.callAsync(makerAddress);
-                const newTakerBalance = await multipleReturnErc20Token.balanceOf.callAsync(takerAddress);
-                expect(newMakerBalance).to.be.bignumber.equal(initialMakerBalance);
-                expect(newTakerBalance).to.be.bignumber.equal(initialTakerBalance);
+                const newFromBalance = await multipleReturnErc20Token.balanceOf.callAsync(fromAddress);
+                const newToBalance = await multipleReturnErc20Token.balanceOf.callAsync(toAddress);
+                expect(newFromBalance).to.be.bignumber.equal(initialFromBalance);
+                expect(newToBalance).to.be.bignumber.equal(initialToBalance);
             });
         });
-
-        it('should have an id of 0xf47261b0', async () => {
-            const proxyId = await erc20Proxy.getProxyId.callAsync();
-            const expectedProxyId = '0xf47261b0';
-            expect(proxyId).to.equal(expectedProxyId);
-        });
     });
 
-    describe('Transfer Proxy - ERC721', () => {
+    describe('ERC721Proxy', () => {
         it('should revert if undefined function is called', async () => {
             const undefinedSelector = '0x01020304';
             await expectTransactionFailedWithoutReasonAsync(
@@ -417,76 +475,81 @@ describe('Asset Transfer Proxies', () => {
                 }),
             );
         });
+        it('should have an id of 0x02571792', async () => {
+            const proxyId = await erc721Proxy.getProxyId.callAsync();
+            const expectedProxyId = '0x02571792';
+            expect(proxyId).to.equal(expectedProxyId);
+        });
         describe('transferFrom', () => {
             it('should successfully transfer tokens', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(1);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
-                const newOwnerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwnerMakerAsset).to.be.bignumber.equal(takerAddress);
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.bignumber.equal(toAddress);
             });
 
             it('should successfully transfer tokens and ignore extra assetData', async () => {
                 // Construct ERC721 asset data
                 const extraData = '0102030405060708';
                 const encodedAssetData = `${assetDataUtils.encodeERC721AssetData(
-                    erc721Token.address,
-                    erc721MakerTokenId,
+                    erc721TokenA.address,
+                    erc721AFromTokenId,
                 )}${extraData}`;
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(1);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Verify transfer was successful
-                const newOwnerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwnerMakerAsset).to.be.bignumber.equal(takerAddress);
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.bignumber.equal(toAddress);
             });
 
             it('should not call onERC721Received when transferring to a smart contract', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(1);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
+                    fromAddress,
                     erc721Receiver.address,
                     amount,
                 );
@@ -495,79 +558,79 @@ describe('Asset Transfer Proxies', () => {
                     await web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                         gas: constants.MAX_TRANSFER_FROM_GAS,
                     }),
                 );
                 // Verify that no log was emitted by erc721 receiver
                 expect(tx.logs.length).to.be.equal(1);
                 // Verify transfer was successful
-                const newOwnerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwnerMakerAsset).to.be.bignumber.equal(erc721Receiver.address);
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.bignumber.equal(erc721Receiver.address);
             });
 
-            it('should throw if transferring 0 amount of a token', async () => {
+            it('should revert if transferring 0 amount of a token', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(0);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await expectTransactionFailedAsync(
                     web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.InvalidAmount,
                 );
-                const newOwner = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwner).to.be.equal(ownerMakerAsset);
+                const newOwner = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwner).to.be.equal(ownerFromAsset);
             });
 
-            it('should throw if transferring > 1 amount of a token', async () => {
+            it('should revert if transferring > 1 amount of a token', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(500);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await expectTransactionFailedAsync(
                     web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.InvalidAmount,
                 );
-                const newOwner = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwner).to.be.equal(ownerMakerAsset);
+                const newOwner = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwner).to.be.equal(ownerFromAsset);
             });
 
-            it('should throw if allowances are too low', async () => {
+            it('should revert if allowances are too low', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Remove transfer approval for makerAddress.
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Remove transfer approval for fromAddress.
                 await web3Wrapper.awaitTransactionSuccessAsync(
-                    await erc721Token.approve.sendTransactionAsync(constants.NULL_ADDRESS, erc721MakerTokenId, {
-                        from: makerAddress,
+                    await erc721TokenA.approve.sendTransactionAsync(constants.NULL_ADDRESS, erc721AFromTokenId, {
+                        from: fromAddress,
                     }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
@@ -575,34 +638,34 @@ describe('Asset Transfer Proxies', () => {
                 const amount = new BigNumber(1);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await expectTransactionFailedAsync(
                     web3Wrapper.sendTransactionAsync({
                         to: erc721Proxy.address,
                         data,
-                        from: exchangeAddress,
+                        from: authorized,
                     }),
                     RevertReason.TransferFailed,
                 );
-                const newOwner = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwner).to.be.equal(ownerMakerAsset);
+                const newOwner = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwner).to.be.equal(ownerFromAsset);
             });
 
-            it('should throw if requesting address is not authorized', async () => {
+            it('should revert if caller is not authorized', async () => {
                 // Construct ERC721 asset data
-                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721Token.address, erc721MakerTokenId);
+                const encodedAssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
                 // Verify pre-condition
-                const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(ownerMakerAsset).to.be.equal(makerAddress);
-                // Perform a transfer from makerAddress to takerAddress
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                // Perform a transfer from fromAddress to toAddress
                 const amount = new BigNumber(1);
                 const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
                     encodedAssetData,
-                    makerAddress,
-                    takerAddress,
+                    fromAddress,
+                    toAddress,
                     amount,
                 );
                 await expectTransactionFailedAsync(
@@ -613,16 +676,570 @@ describe('Asset Transfer Proxies', () => {
                     }),
                     RevertReason.SenderNotAuthorized,
                 );
-                const newOwner = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
-                expect(newOwner).to.be.equal(ownerMakerAsset);
+                const newOwner = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwner).to.be.equal(ownerFromAsset);
             });
         });
-
-        it('should have an id of 0x02571792', async () => {
-            const proxyId = await erc721Proxy.getProxyId.callAsync();
-            const expectedProxyId = '0x02571792';
+    });
+    describe('MultiAssetProxy', () => {
+        it('should revert if undefined function is called', async () => {
+            const undefinedSelector = '0x01020304';
+            await expectTransactionFailedWithoutReasonAsync(
+                web3Wrapper.sendTransactionAsync({
+                    from: owner,
+                    to: multiAssetProxy.address,
+                    value: constants.ZERO_AMOUNT,
+                    data: undefinedSelector,
+                }),
+            );
+        });
+        it('should have an id of 0x94cfcdd7', async () => {
+            const proxyId = await multiAssetProxy.getProxyId.callAsync();
+            // first 4 bytes of `keccak256('MultiAsset(uint256[],bytes[])')`
+            const expectedProxyId = '0x94cfcdd7';
             expect(proxyId).to.equal(expectedProxyId);
         });
+        describe('transferFrom', () => {
+            it('should transfer a single ERC20 token', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const amounts = [erc20Amount];
+                const nestedAssetData = [erc20AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalAmount = inputAmount.times(erc20Amount);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalAmount),
+                );
+            });
+            it('should successfully transfer multiple of the same ERC20 token', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount1 = new BigNumber(10);
+                const erc20Amount2 = new BigNumber(20);
+                const erc20AssetData1 = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc20AssetData2 = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const amounts = [erc20Amount1, erc20Amount2];
+                const nestedAssetData = [erc20AssetData1, erc20AssetData2];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalAmount = inputAmount.times(erc20Amount1).plus(inputAmount.times(erc20Amount2));
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalAmount),
+                );
+            });
+            it('should successfully transfer multiple different ERC20 tokens', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount1 = new BigNumber(10);
+                const erc20Amount2 = new BigNumber(20);
+                const erc20AssetData1 = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc20AssetData2 = assetDataUtils.encodeERC20AssetData(erc20TokenB.address);
+                const amounts = [erc20Amount1, erc20Amount2];
+                const nestedAssetData = [erc20AssetData1, erc20AssetData2];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalErc20AAmount = inputAmount.times(erc20Amount1);
+                const totalErc20BAmount = inputAmount.times(erc20Amount2);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalErc20AAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalErc20AAmount),
+                );
+                expect(newBalances[fromAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenB.address].minus(totalErc20BAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenB.address].add(totalErc20BAmount),
+                );
+            });
+            it('should transfer a single ERC721 token', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc721Amount];
+                const nestedAssetData = [erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.equal(toAddress);
+            });
+            it('should successfully transfer multiple of the same ERC721 token', async () => {
+                const erc721Balances = await erc721Wrapper.getBalancesAsync();
+                const erc721AFromTokenId2 = erc721Balances[fromAddress][erc721TokenA.address][1];
+                const erc721AssetData1 = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const erc721AssetData2 = assetDataUtils.encodeERC721AssetData(
+                    erc721TokenA.address,
+                    erc721AFromTokenId2,
+                );
+                const inputAmount = new BigNumber(1);
+                const erc721Amount = new BigNumber(1);
+                const amounts = [erc721Amount, erc721Amount];
+                const nestedAssetData = [erc721AssetData1, erc721AssetData2];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const ownerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset1).to.be.equal(fromAddress);
+                const ownerFromAsset2 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId2);
+                expect(ownerFromAsset2).to.be.equal(fromAddress);
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                        gas: constants.MAX_TRANSFER_FROM_GAS,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newOwnerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                const newOwnerFromAsset2 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId2);
+                expect(newOwnerFromAsset1).to.be.equal(toAddress);
+                expect(newOwnerFromAsset2).to.be.equal(toAddress);
+            });
+            it('should successfully transfer multiple different ERC721 tokens', async () => {
+                const erc721AssetData1 = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const erc721AssetData2 = assetDataUtils.encodeERC721AssetData(erc721TokenB.address, erc721BFromTokenId);
+                const inputAmount = new BigNumber(1);
+                const erc721Amount = new BigNumber(1);
+                const amounts = [erc721Amount, erc721Amount];
+                const nestedAssetData = [erc721AssetData1, erc721AssetData2];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const ownerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset1).to.be.equal(fromAddress);
+                const ownerFromAsset2 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId);
+                expect(ownerFromAsset2).to.be.equal(fromAddress);
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                        gas: constants.MAX_TRANSFER_FROM_GAS,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newOwnerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                const newOwnerFromAsset2 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId);
+                expect(newOwnerFromAsset1).to.be.equal(toAddress);
+                expect(newOwnerFromAsset2).to.be.equal(toAddress);
+            });
+            it('should successfully transfer a combination of ERC20 and ERC721 tokens', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalAmount = inputAmount.times(erc20Amount);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalAmount),
+                );
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.equal(toAddress);
+            });
+            it('should successfully transfer tokens and ignore extra assetData', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const extraData = '0102030405060708';
+                const assetData = `${assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                    amounts,
+                    nestedAssetData,
+                )}${extraData}`;
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                const ownerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset).to.be.equal(fromAddress);
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalAmount = inputAmount.times(erc20Amount);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalAmount),
+                );
+                const newOwnerFromAsset = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(newOwnerFromAsset).to.be.equal(toAddress);
+            });
+            it('should successfully transfer correct amounts when the `amount` > 1', async () => {
+                const inputAmount = new BigNumber(100);
+                const erc20Amount1 = new BigNumber(10);
+                const erc20Amount2 = new BigNumber(20);
+                const erc20AssetData1 = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc20AssetData2 = assetDataUtils.encodeERC20AssetData(erc20TokenB.address);
+                const amounts = [erc20Amount1, erc20Amount2];
+                const nestedAssetData = [erc20AssetData1, erc20AssetData2];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalErc20AAmount = inputAmount.times(erc20Amount1);
+                const totalErc20BAmount = inputAmount.times(erc20Amount2);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalErc20AAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalErc20AAmount),
+                );
+                expect(newBalances[fromAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenB.address].minus(totalErc20BAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenB.address].add(totalErc20BAmount),
+                );
+            });
+            it('should successfully transfer a large amount of tokens', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount1 = new BigNumber(10);
+                const erc20Amount2 = new BigNumber(20);
+                const erc20AssetData1 = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc20AssetData2 = assetDataUtils.encodeERC20AssetData(erc20TokenB.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721Balances = await erc721Wrapper.getBalancesAsync();
+                const erc721AFromTokenId2 = erc721Balances[fromAddress][erc721TokenA.address][1];
+                const erc721BFromTokenId2 = erc721Balances[fromAddress][erc721TokenB.address][1];
+                const erc721AssetData1 = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const erc721AssetData2 = assetDataUtils.encodeERC721AssetData(
+                    erc721TokenA.address,
+                    erc721AFromTokenId2,
+                );
+                const erc721AssetData3 = assetDataUtils.encodeERC721AssetData(erc721TokenB.address, erc721BFromTokenId);
+                const erc721AssetData4 = assetDataUtils.encodeERC721AssetData(
+                    erc721TokenB.address,
+                    erc721BFromTokenId2,
+                );
+                const amounts = [erc721Amount, erc20Amount1, erc721Amount, erc20Amount2, erc721Amount, erc721Amount];
+                const nestedAssetData = [
+                    erc721AssetData1,
+                    erc20AssetData1,
+                    erc721AssetData2,
+                    erc20AssetData2,
+                    erc721AssetData3,
+                    erc721AssetData4,
+                ];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                const ownerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                expect(ownerFromAsset1).to.be.equal(fromAddress);
+                const ownerFromAsset2 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId2);
+                expect(ownerFromAsset2).to.be.equal(fromAddress);
+                const ownerFromAsset3 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId);
+                expect(ownerFromAsset3).to.be.equal(fromAddress);
+                const ownerFromAsset4 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId2);
+                expect(ownerFromAsset4).to.be.equal(fromAddress);
+                const erc20Balances = await erc20Wrapper.getBalancesAsync();
+                await web3Wrapper.awaitTransactionSuccessAsync(
+                    await web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                        gas: constants.MAX_EXECUTE_TRANSACTION_GAS,
+                    }),
+                    constants.AWAIT_TRANSACTION_MINED_MS,
+                );
+                const newOwnerFromAsset1 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId);
+                const newOwnerFromAsset2 = await erc721TokenA.ownerOf.callAsync(erc721AFromTokenId2);
+                const newOwnerFromAsset3 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId);
+                const newOwnerFromAsset4 = await erc721TokenB.ownerOf.callAsync(erc721BFromTokenId2);
+                expect(newOwnerFromAsset1).to.be.equal(toAddress);
+                expect(newOwnerFromAsset2).to.be.equal(toAddress);
+                expect(newOwnerFromAsset3).to.be.equal(toAddress);
+                expect(newOwnerFromAsset4).to.be.equal(toAddress);
+                const newBalances = await erc20Wrapper.getBalancesAsync();
+                const totalErc20AAmount = inputAmount.times(erc20Amount1);
+                const totalErc20BAmount = inputAmount.times(erc20Amount2);
+                expect(newBalances[fromAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenA.address].minus(totalErc20AAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenA.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenA.address].add(totalErc20AAmount),
+                );
+                expect(newBalances[fromAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[fromAddress][erc20TokenB.address].minus(totalErc20BAmount),
+                );
+                expect(newBalances[toAddress][erc20TokenB.address]).to.be.bignumber.equal(
+                    erc20Balances[toAddress][erc20TokenB.address].add(totalErc20BAmount),
+                );
+            });
+            it('should revert if a single transfer fails', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                // 2 is an invalid erc721 amount
+                const erc721Amount = new BigNumber(2);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    RevertReason.InvalidAmount,
+                );
+            });
+            it('should revert if an AssetProxy is not registered', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const invalidProxyId = '0x12345678';
+                const invalidErc721AssetData = `${invalidProxyId}${erc721AssetData.slice(10)}`;
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, invalidErc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    RevertReason.AssetProxyDoesNotExist,
+                );
+            });
+            it('should revert if the length of `amounts` does not match the length of `nestedAssetData`', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc20Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    RevertReason.LengthMismatch,
+                );
+            });
+            it('should revert if amounts multiplication results in an overflow', async () => {
+                const inputAmount = new BigNumber(2).pow(128);
+                const erc20Amount = new BigNumber(2).pow(128);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const amounts = [erc20Amount];
+                const nestedAssetData = [erc20AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    RevertReason.Uint256Overflow,
+                );
+            });
+            it('should revert if an element of `nestedAssetData` is < 4 bytes long', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = '0x123456';
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: authorized,
+                    }),
+                    RevertReason.LengthGreaterThan3Required,
+                );
+            });
+            it('should revert if caller is not authorized', async () => {
+                const inputAmount = new BigNumber(1);
+                const erc20Amount = new BigNumber(10);
+                const erc20AssetData = assetDataUtils.encodeERC20AssetData(erc20TokenA.address);
+                const erc721Amount = new BigNumber(1);
+                const erc721AssetData = assetDataUtils.encodeERC721AssetData(erc721TokenA.address, erc721AFromTokenId);
+                const amounts = [erc20Amount, erc721Amount];
+                const nestedAssetData = [erc20AssetData, erc721AssetData];
+                const assetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(amounts, nestedAssetData);
+                const data = assetProxyInterface.transferFrom.getABIEncodedTransactionData(
+                    assetData,
+                    fromAddress,
+                    toAddress,
+                    inputAmount,
+                );
+                await expectTransactionFailedAsync(
+                    web3Wrapper.sendTransactionAsync({
+                        to: multiAssetProxy.address,
+                        data,
+                        from: notAuthorized,
+                    }),
+                    RevertReason.SenderNotAuthorized,
+                );
+            });
+        });
     });
 });
 // tslint:enable:no-unnecessary-type-assertion
diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index fc8dc5346..9159b0d8f 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -14,6 +14,8 @@ import { DummyNoReturnERC20TokenContract } from '../../generated-wrappers/dummy_
 import { ERC20ProxyContract } from '../../generated-wrappers/erc20_proxy';
 import { ERC721ProxyContract } from '../../generated-wrappers/erc721_proxy';
 import { ExchangeCancelEventArgs, ExchangeContract } from '../../generated-wrappers/exchange';
+import { IAssetDataContract } from '../../generated-wrappers/i_asset_data';
+import { MultiAssetProxyContract } from '../../generated-wrappers/multi_asset_proxy';
 import { ReentrantERC20TokenContract } from '../../generated-wrappers/reentrant_erc20_token';
 import { TestStaticCallReceiverContract } from '../../generated-wrappers/test_static_call_receiver';
 import { artifacts } from '../../src/artifacts';
@@ -31,6 +33,11 @@ import { provider, txDefaults, web3Wrapper } from '../utils/web3_wrapper';
 chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+const assetDataInterface = new IAssetDataContract(
+    artifacts.IAssetData.compilerOutput.abi,
+    constants.NULL_ADDRESS,
+    provider,
+);
 // tslint:disable:no-unnecessary-type-assertion
 describe('Exchange core', () => {
     let makerAddress: string;
@@ -47,6 +54,7 @@ describe('Exchange core', () => {
     let exchange: ExchangeContract;
     let erc20Proxy: ERC20ProxyContract;
     let erc721Proxy: ERC721ProxyContract;
+    let multiAssetProxy: MultiAssetProxyContract;
     let maliciousWallet: TestStaticCallReceiverContract;
     let maliciousValidator: TestStaticCallReceiverContract;
 
@@ -76,31 +84,39 @@ describe('Exchange core', () => {
         erc20Wrapper = new ERC20Wrapper(provider, usedAddresses, owner);
         erc721Wrapper = new ERC721Wrapper(provider, usedAddresses, owner);
 
+        // Deploy AssetProxies, Exchange, tokens, and malicious contracts
+        erc20Proxy = await erc20Wrapper.deployProxyAsync();
+        erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        multiAssetProxy = await MultiAssetProxyContract.deployFrom0xArtifactAsync(
+            artifacts.MultiAssetProxy,
+            provider,
+            txDefaults,
+        );
         const numDummyErc20ToDeploy = 3;
         [erc20TokenA, erc20TokenB, zrxToken] = await erc20Wrapper.deployDummyTokensAsync(
             numDummyErc20ToDeploy,
             constants.DUMMY_TOKEN_DECIMALS,
         );
-        erc20Proxy = await erc20Wrapper.deployProxyAsync();
-        await erc20Wrapper.setBalancesAndAllowancesAsync();
-
         [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
-        erc721Proxy = await erc721Wrapper.deployProxyAsync();
-        await erc721Wrapper.setBalancesAndAllowancesAsync();
-        const erc721Balances = await erc721Wrapper.getBalancesAsync();
-        erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
-        erc721TakerAssetIds = erc721Balances[takerAddress][erc721Token.address];
-
         exchange = await ExchangeContract.deployFrom0xArtifactAsync(
             artifacts.Exchange,
             provider,
             txDefaults,
             assetDataUtils.encodeERC20AssetData(zrxToken.address),
         );
-        exchangeWrapper = new ExchangeWrapper(exchange, provider);
-        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
-        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+        maliciousWallet = maliciousValidator = await TestStaticCallReceiverContract.deployFrom0xArtifactAsync(
+            artifacts.TestStaticCallReceiver,
+            provider,
+            txDefaults,
+        );
+        reentrantErc20Token = await ReentrantERC20TokenContract.deployFrom0xArtifactAsync(
+            artifacts.ReentrantERC20Token,
+            provider,
+            txDefaults,
+            exchange.address,
+        );
 
+        // Configure ERC20Proxy
         await web3Wrapper.awaitTransactionSuccessAsync(
             await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
                 from: owner,
@@ -108,27 +124,64 @@ describe('Exchange core', () => {
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
         await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(multiAssetProxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+
+        // Configure ERC721Proxy
+        await web3Wrapper.awaitTransactionSuccessAsync(
             await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
                 from: owner,
             }),
             constants.AWAIT_TRANSACTION_MINED_MS,
         );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(multiAssetProxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
 
-        maliciousWallet = maliciousValidator = await TestStaticCallReceiverContract.deployFrom0xArtifactAsync(
-            artifacts.TestStaticCallReceiver,
-            provider,
-            txDefaults,
+        // Configure MultiAssetProxy
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
         );
-        reentrantErc20Token = await ReentrantERC20TokenContract.deployFrom0xArtifactAsync(
-            artifacts.ReentrantERC20Token,
-            provider,
-            txDefaults,
-            exchange.address,
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
+        );
+        await web3Wrapper.awaitTransactionSuccessAsync(
+            await multiAssetProxy.registerAssetProxy.sendTransactionAsync(erc721Proxy.address, {
+                from: owner,
+            }),
+            constants.AWAIT_TRANSACTION_MINED_MS,
         );
 
+        // Configure Exchange
+        exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(multiAssetProxy.address, owner);
+
+        // Configure ERC20 tokens
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
+
+        // Configure ERC721 tokens
+        await erc721Wrapper.setBalancesAndAllowancesAsync();
+        const erc721Balances = await erc721Wrapper.getBalancesAsync();
+        erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
+        erc721TakerAssetIds = erc721Balances[takerAddress][erc721Token.address];
+
+        // Configure order defaults
         defaultMakerAssetAddress = erc20TokenA.address;
         defaultTakerAssetAddress = erc20TokenB.address;
-
         const defaultOrderParams = {
             ...constants.STATIC_ORDER_PARAMS,
             exchangeAddress: exchange.address,
@@ -707,6 +760,292 @@ describe('Exchange core', () => {
         });
     });
 
+    describe('Testing exchange of multiple assets', () => {
+        it('should allow multiple assets to be exchanged for a single asset', async () => {
+            const makerAmounts = [new BigNumber(10), new BigNumber(20)];
+            const makerNestedAssetData = [
+                assetDataUtils.encodeERC20AssetData(erc20TokenA.address),
+                assetDataUtils.encodeERC20AssetData(erc20TokenB.address),
+            ];
+            const makerAssetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                makerAmounts,
+                makerNestedAssetData,
+            );
+            const makerAssetAmount = new BigNumber(1);
+            const takerAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
+            const takerAssetAmount = new BigNumber(10);
+            signedOrder = await orderFactory.newSignedOrderAsync({
+                makerAssetData,
+                takerAssetData,
+                makerAssetAmount,
+                takerAssetAmount,
+                makerFee: constants.ZERO_AMOUNT,
+                takerFee: constants.ZERO_AMOUNT,
+            });
+
+            const initialMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const initialMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const initialMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const initialTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const initialTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const initialTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
+
+            const finalMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const finalMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const finalMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const finalTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const finalTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const finalTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            expect(finalMakerBalanceA).to.be.bignumber.equal(
+                initialMakerBalanceA.minus(makerAmounts[0].times(makerAssetAmount)),
+            );
+            expect(finalMakerBalanceB).to.be.bignumber.equal(
+                initialMakerBalanceB.minus(makerAmounts[1].times(makerAssetAmount)),
+            );
+            expect(finalMakerZrxBalance).to.be.bignumber.equal(initialMakerZrxBalance.plus(takerAssetAmount));
+            expect(finalTakerBalanceA).to.be.bignumber.equal(
+                initialTakerBalanceA.plus(makerAmounts[0].times(makerAssetAmount)),
+            );
+            expect(finalTakerBalanceB).to.be.bignumber.equal(
+                initialTakerBalanceB.plus(makerAmounts[1].times(makerAssetAmount)),
+            );
+            expect(finalTakerZrxBalance).to.be.bignumber.equal(initialTakerZrxBalance.minus(takerAssetAmount));
+        });
+        it('should allow multiple assets to be exchanged for multiple assets', async () => {
+            const makerAmounts = [new BigNumber(10), new BigNumber(20)];
+            const makerNestedAssetData = [
+                assetDataUtils.encodeERC20AssetData(erc20TokenA.address),
+                assetDataUtils.encodeERC20AssetData(erc20TokenB.address),
+            ];
+            const makerAssetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                makerAmounts,
+                makerNestedAssetData,
+            );
+            const makerAssetAmount = new BigNumber(1);
+            const takerAmounts = [new BigNumber(10), new BigNumber(1)];
+            const takerAssetId = erc721TakerAssetIds[0];
+            const takerNestedAssetData = [
+                assetDataUtils.encodeERC20AssetData(zrxToken.address),
+                assetDataUtils.encodeERC721AssetData(erc721Token.address, takerAssetId),
+            ];
+            const takerAssetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                takerAmounts,
+                takerNestedAssetData,
+            );
+            const takerAssetAmount = new BigNumber(1);
+            signedOrder = await orderFactory.newSignedOrderAsync({
+                makerAssetData,
+                takerAssetData,
+                makerAssetAmount,
+                takerAssetAmount,
+                makerFee: constants.ZERO_AMOUNT,
+                takerFee: constants.ZERO_AMOUNT,
+            });
+
+            const initialMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const initialMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const initialMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const initialTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const initialTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const initialTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+            const initialOwnerTakerAsset = await erc721Token.ownerOf.callAsync(takerAssetId);
+            expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
+
+            await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
+
+            const finalMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const finalMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const finalMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const finalTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const finalTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const finalTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+            const finalOwnerTakerAsset = await erc721Token.ownerOf.callAsync(takerAssetId);
+
+            expect(finalMakerBalanceA).to.be.bignumber.equal(
+                initialMakerBalanceA.minus(makerAmounts[0].times(makerAssetAmount)),
+            );
+            expect(finalMakerBalanceB).to.be.bignumber.equal(
+                initialMakerBalanceB.minus(makerAmounts[1].times(makerAssetAmount)),
+            );
+            expect(finalMakerZrxBalance).to.be.bignumber.equal(
+                initialMakerZrxBalance.plus(takerAmounts[0].times(takerAssetAmount)),
+            );
+            expect(finalTakerBalanceA).to.be.bignumber.equal(
+                initialTakerBalanceA.plus(makerAmounts[0].times(makerAssetAmount)),
+            );
+            expect(finalTakerBalanceB).to.be.bignumber.equal(
+                initialTakerBalanceB.plus(makerAmounts[1].times(makerAssetAmount)),
+            );
+            expect(finalTakerZrxBalance).to.be.bignumber.equal(
+                initialTakerZrxBalance.minus(takerAmounts[0].times(takerAssetAmount)),
+            );
+            expect(finalOwnerTakerAsset).to.be.equal(makerAddress);
+        });
+        it('should allow an order selling multiple assets to be partially filled', async () => {
+            const makerAmounts = [new BigNumber(10), new BigNumber(20)];
+            const makerNestedAssetData = [
+                assetDataUtils.encodeERC20AssetData(erc20TokenA.address),
+                assetDataUtils.encodeERC20AssetData(erc20TokenB.address),
+            ];
+            const makerAssetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                makerAmounts,
+                makerNestedAssetData,
+            );
+            const makerAssetAmount = new BigNumber(30);
+            const takerAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
+            const takerAssetAmount = new BigNumber(10);
+            signedOrder = await orderFactory.newSignedOrderAsync({
+                makerAssetData,
+                takerAssetData,
+                makerAssetAmount,
+                takerAssetAmount,
+                makerFee: constants.ZERO_AMOUNT,
+                takerFee: constants.ZERO_AMOUNT,
+            });
+
+            const initialMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const initialMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const initialMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const initialTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const initialTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const initialTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            const takerAssetFillAmount = takerAssetAmount.dividedToIntegerBy(2);
+            await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, {
+                takerAssetFillAmount,
+            });
+
+            const finalMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const finalMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const finalMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const finalTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const finalTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const finalTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            expect(finalMakerBalanceA).to.be.bignumber.equal(
+                initialMakerBalanceA.minus(
+                    makerAmounts[0].times(
+                        makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalMakerBalanceB).to.be.bignumber.equal(
+                initialMakerBalanceB.minus(
+                    makerAmounts[1].times(
+                        makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalMakerZrxBalance).to.be.bignumber.equal(
+                initialMakerZrxBalance.plus(
+                    takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                ),
+            );
+            expect(finalTakerBalanceA).to.be.bignumber.equal(
+                initialTakerBalanceA.plus(
+                    makerAmounts[0].times(
+                        makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalTakerBalanceB).to.be.bignumber.equal(
+                initialTakerBalanceB.plus(
+                    makerAmounts[1].times(
+                        makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalTakerZrxBalance).to.be.bignumber.equal(
+                initialTakerZrxBalance.minus(
+                    takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                ),
+            );
+        });
+        it('should allow an order buying multiple assets to be partially filled', async () => {
+            const takerAmounts = [new BigNumber(10), new BigNumber(20)];
+            const takerNestedAssetData = [
+                assetDataUtils.encodeERC20AssetData(erc20TokenA.address),
+                assetDataUtils.encodeERC20AssetData(erc20TokenB.address),
+            ];
+            const takerAssetData = assetDataInterface.MultiAsset.getABIEncodedTransactionData(
+                takerAmounts,
+                takerNestedAssetData,
+            );
+            const takerAssetAmount = new BigNumber(30);
+            const makerAssetData = assetDataUtils.encodeERC20AssetData(zrxToken.address);
+            const makerAssetAmount = new BigNumber(10);
+            signedOrder = await orderFactory.newSignedOrderAsync({
+                makerAssetData,
+                takerAssetData,
+                makerAssetAmount,
+                takerAssetAmount,
+                makerFee: constants.ZERO_AMOUNT,
+                takerFee: constants.ZERO_AMOUNT,
+            });
+
+            const initialMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const initialMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const initialMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const initialTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const initialTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const initialTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            const takerAssetFillAmount = takerAssetAmount.dividedToIntegerBy(2);
+            await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, {
+                takerAssetFillAmount,
+            });
+
+            const finalMakerBalanceA = await erc20TokenA.balanceOf.callAsync(makerAddress);
+            const finalMakerBalanceB = await erc20TokenB.balanceOf.callAsync(makerAddress);
+            const finalMakerZrxBalance = await zrxToken.balanceOf.callAsync(makerAddress);
+            const finalTakerBalanceA = await erc20TokenA.balanceOf.callAsync(takerAddress);
+            const finalTakerBalanceB = await erc20TokenB.balanceOf.callAsync(takerAddress);
+            const finalTakerZrxBalance = await zrxToken.balanceOf.callAsync(takerAddress);
+
+            expect(finalMakerBalanceA).to.be.bignumber.equal(
+                initialMakerBalanceA.plus(
+                    takerAmounts[0].times(
+                        takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalMakerBalanceB).to.be.bignumber.equal(
+                initialMakerBalanceB.plus(
+                    takerAmounts[1].times(
+                        takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalMakerZrxBalance).to.be.bignumber.equal(
+                initialMakerZrxBalance.minus(
+                    makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                ),
+            );
+            expect(finalTakerBalanceA).to.be.bignumber.equal(
+                initialTakerBalanceA.minus(
+                    takerAmounts[0].times(
+                        takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalTakerBalanceB).to.be.bignumber.equal(
+                initialTakerBalanceB.minus(
+                    takerAmounts[1].times(
+                        takerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                    ),
+                ),
+            );
+            expect(finalTakerZrxBalance).to.be.bignumber.equal(
+                initialTakerZrxBalance.plus(
+                    makerAssetAmount.times(takerAssetFillAmount).dividedToIntegerBy(takerAssetAmount),
+                ),
+            );
+        });
+    });
+
     describe('getOrderInfo', () => {
         beforeEach(async () => {
             signedOrder = await orderFactory.newSignedOrderAsync();
diff --git a/packages/contracts/test/utils/constants.ts b/packages/contracts/test/utils/constants.ts
index cd21330e9..d2c3ab512 100644
--- a/packages/contracts/test/utils/constants.ts
+++ b/packages/contracts/test/utils/constants.ts
@@ -35,7 +35,7 @@ export const constants = {
     DUMMY_TOKEN_TOTAL_SUPPLY: new BigNumber(0),
     NULL_BYTES: '0x',
     NUM_DUMMY_ERC20_TO_DEPLOY: 3,
-    NUM_DUMMY_ERC721_TO_DEPLOY: 1,
+    NUM_DUMMY_ERC721_TO_DEPLOY: 2,
     NUM_ERC721_TOKENS_TO_MINT: 2,
     NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
     UNLIMITED_ALLOWANCE_IN_BASE_UNITS: new BigNumber(2).pow(256).minus(1),
diff --git a/packages/contracts/test/utils/erc721_wrapper.ts b/packages/contracts/test/utils/erc721_wrapper.ts
index 3ef4e701d..e9da553d0 100644
--- a/packages/contracts/test/utils/erc721_wrapper.ts
+++ b/packages/contracts/test/utils/erc721_wrapper.ts
@@ -29,7 +29,8 @@ export class ERC721Wrapper {
         this._contractOwnerAddress = contractOwnerAddress;
     }
     public async deployDummyTokensAsync(): Promise<DummyERC721TokenContract[]> {
-        for (let i = 0; i < constants.NUM_DUMMY_ERC721_TO_DEPLOY; i++) {
+        // tslint:disable-next-line:no-unused-variable
+        for (const i of _.times(constants.NUM_DUMMY_ERC721_TO_DEPLOY)) {
             this._dummyTokenContracts.push(
                 await DummyERC721TokenContract.deployFrom0xArtifactAsync(
                     artifacts.DummyERC721Token,
@@ -61,7 +62,8 @@ export class ERC721Wrapper {
         this._initialTokenIdsByOwner = {};
         for (const dummyTokenContract of this._dummyTokenContracts) {
             for (const tokenOwnerAddress of this._tokenOwnerAddresses) {
-                for (let i = 0; i < constants.NUM_ERC721_TOKENS_TO_MINT; i++) {
+                // tslint:disable-next-line:no-unused-variable
+                for (const i of _.times(constants.NUM_ERC721_TOKENS_TO_MINT)) {
                     const tokenId = generatePseudoRandomSalt();
                     await this.mintAsync(dummyTokenContract.address, tokenId, tokenOwnerAddress);
                     if (_.isUndefined(this._initialTokenIdsByOwner[tokenOwnerAddress])) {
diff --git a/packages/contracts/tsconfig.json b/packages/contracts/tsconfig.json
index 8b29365cc..e0f85079a 100644
--- a/packages/contracts/tsconfig.json
+++ b/packages/contracts/tsconfig.json
@@ -26,6 +26,7 @@
         "./generated-artifacts/IWallet.json",
         "./generated-artifacts/InvalidERC721Receiver.json",
         "./generated-artifacts/MixinAuthorizable.json",
+        "./generated-artifacts/MultiAssetProxy.json",
         "./generated-artifacts/MultiSigWallet.json",
         "./generated-artifacts/MultiSigWalletWithTimeLock.json",
         "./generated-artifacts/OrderValidator.json",
diff --git a/packages/types/CHANGELOG.json b/packages/types/CHANGELOG.json
index 0b32b60f0..53b24aff0 100644
--- a/packages/types/CHANGELOG.json
+++ b/packages/types/CHANGELOG.json
@@ -1,5 +1,14 @@
 [
     {
+        "version": "1.4.0",
+        "changes": [
+            {
+                "note": "Add `LengthMismatch` and `LengthGreaterThan3Required` revert reasons",
+                "pr": 1224
+            }
+        ]
+    },
+    {
         "version": "1.3.0",
         "changes": [
             {
diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index 1a86f45e6..26d8f8e22 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -195,6 +195,7 @@ export enum RevertReason {
     FailedExecution = 'FAILED_EXECUTION',
     AssetProxyAlreadyExists = 'ASSET_PROXY_ALREADY_EXISTS',
     LengthGreaterThan0Required = 'LENGTH_GREATER_THAN_0_REQUIRED',
+    LengthGreaterThan3Required = 'LENGTH_GREATER_THAN_3_REQUIRED',
     LengthGreaterThan131Required = 'LENGTH_GREATER_THAN_131_REQUIRED',
     Length0Required = 'LENGTH_0_REQUIRED',
     Length65Required = 'LENGTH_65_REQUIRED',
@@ -209,6 +210,7 @@ export enum RevertReason {
     MakerNotWhitelisted = 'MAKER_NOT_WHITELISTED',
     TakerNotWhitelisted = 'TAKER_NOT_WHITELISTED',
     AssetProxyDoesNotExist = 'ASSET_PROXY_DOES_NOT_EXIST',
+    LengthMismatch = 'LENGTH_MISMATCH',
     LibBytesGreaterThanZeroLengthRequired = 'GREATER_THAN_ZERO_LENGTH_REQUIRED',
     LibBytesGreaterOrEqualTo4LengthRequired = 'GREATER_OR_EQUAL_TO_4_LENGTH_REQUIRED',
     LibBytesGreaterOrEqualTo20LengthRequired = 'GREATER_OR_EQUAL_TO_20_LENGTH_REQUIRED',