diff --git a/README.md b/README.md
index 654e97a..d772a8e 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@ Features not supported:
 - signing transactions
 - managing storage (neither in node.js or the browser)
 
-## API
+## Wallet API
 
 Constructors:
 
@@ -54,6 +54,27 @@ Instance methods:
 
 All of the above instance methods return a Buffer or JSON. Use the `String` suffixed versions for a string output, such as `getPrivateKeyString()`.
 
+## HD Wallet API
+
+To use BIP32 HD wallets, first include the `hdkey` submodule:
+
+`var hdkey = require('ethereumjs-wallet/hdkey')`
+
+Constructors:
+
+* `fromMasterSeed(seed)` - create an instance based on a seed
+* `formExtendedKey(key)` - create an instance based on a BIP32 extended private or public key
+
+For the seed  we suggest to use [bip39](https://npmjs.org/packages/bip39) to create one from a BIP39 mnemonic.
+
+Instance methods:
+
+* `privateExtendedKey()` - return a BIP32 extended private key
+* `publicExtendedKey()` - return a BIP32 extended private key
+* `derivePath(path)` - derive a node based on a path (e.g.  m/44'/0'/0/1)
+* `deriveChild(index)` - derive a node based on a child index
+* `getWallet()` - return a `Wallet` instance as seen above
+
 ### Remarks about `toV3`
 
 The `options` is an optional object hash, where all the serialization parameters can be fine tuned:
@@ -82,3 +103,9 @@ The following settings are favoured by the Go Ethereum implementation and we def
 - `r`: `8`
 - `p`: `1`
 - `cipher`: `aes-128-ctr`
+
+## License
+
+MIT License
+
+Copyright (C) 2016 Alex Beregszaszi
diff --git a/hdkey.js b/hdkey.js
new file mode 100644
index 0000000..5089d0d
--- /dev/null
+++ b/hdkey.js
@@ -0,0 +1,48 @@
+const HDKey = require('hdkey')
+const Wallet = require('./index.js')
+
+function EthereumHDKey () {
+}
+
+/*
+ * Horrible wrapping.
+ */
+function fromHDKey (hdkey) {
+  var ret = new EthereumHDKey()
+  ret._hdkey = hdkey
+  return ret
+}
+
+EthereumHDKey.fromMasterSeed = function (seedBuffer) {
+  return fromHDKey(HDKey.fromMasterSeed(seedBuffer))
+}
+
+EthereumHDKey.fromExtendedKey = function (base58key) {
+  return fromHDKey(HDKey.fromExtendedKey(base58key))
+}
+
+EthereumHDKey.prototype.privateExtendedKey = function () {
+  return this._hdkey.privateExtendedKey
+}
+
+EthereumHDKey.prototype.publicExtendedKey = function () {
+  return this._hdkey.publicExtendedKey
+}
+
+EthereumHDKey.prototype.derivePath = function (path) {
+  return fromHDKey(this._hdkey.derive(path))
+}
+
+EthereumHDKey.prototype.deriveChild = function (index) {
+  return fromHDKey(this._hdkey.deriveChild(index))
+}
+
+EthereumHDKey.prototype.getWallet = function () {
+  if (this._hdkey._privateKey) {
+    return Wallet.fromPrivateKey(this._hdkey._privateKey)
+  } else {
+    return Wallet.fromPublicKey(this._hdkey._publicKey)
+  }
+}
+
+module.exports = EthereumHDKey
diff --git a/package.json b/package.json
index ab59fd0..59356cf 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,7 @@
   "scripts": {
     "lint": "standard",
     "prepublish": "npm run lint && npm run test",
-    "test": "mocha ./test/index.js"
+    "test": "mocha ./test/index.js && mocha ./test/hdkey.js"
   },
   "repository": {
     "type": "git",
@@ -27,6 +27,7 @@
     "aes-js": "^0.2.3",
     "bs58check": "^1.0.8",
     "ethereumjs-util": "^4.3.0",
+    "hdkey": "git+https://github.com/axic/hdkey#feature/secp256k1",
     "scrypt.js": "^0.1.0",
     "secp256k1": "^3.0.1",
     "uuid": "^2.0.1",
diff --git a/test/hdkey.js b/test/hdkey.js
new file mode 100644
index 0000000..950c273
--- /dev/null
+++ b/test/hdkey.js
@@ -0,0 +1,74 @@
+var assert = require('assert')
+var HDKey = require('../hdkey.js')
+
+// from BIP39 mnemonic: awake book subject inch gentle blur grant damage process float month clown
+var fixtureseed = new Buffer('747f302d9c916698912d5f70be53a6cf53bc495803a5523d3a7c3afa2afba94ec3803f838b3e1929ab5481f9da35441372283690fdcf27372c38f40ba134fe03', 'hex')
+var fixturehd = HDKey.fromMasterSeed(fixtureseed)
+
+describe('.fromMasterSeed()', function () {
+  it('should work', function () {
+    assert.doesNotThrow(function () {
+      HDKey.fromMasterSeed(fixtureseed)
+    })
+  })
+})
+
+describe('.privateExtendedKey()', function () {
+  it('should work', function () {
+    assert.equal(fixturehd.privateExtendedKey(), 'xprv9s21ZrQH143K4KqQx9Zrf1eN8EaPQVFxM2Ast8mdHn7GKiDWzNEyNdduJhWXToy8MpkGcKjxeFWd8oBSvsz4PCYamxR7TX49pSpp3bmHVAY')
+  })
+})
+
+describe('.publicExtendedKey()', function () {
+  it('should work', function () {
+    assert.equal(fixturehd.publicExtendedKey(), 'xpub661MyMwAqRbcGout4B6s29b6gGQsowyoiF6UgXBEr7eFCWYfXuZDvRxP9zEh1Kwq3TLqDQMbkbaRpSnoC28oWvjLeshoQz1StZ9YHM1EpcJ')
+  })
+})
+
+describe('.fromExtendedKey()', function () {
+  it('should work with public', function () {
+    var hdnode = HDKey.fromExtendedKey('xpub661MyMwAqRbcGout4B6s29b6gGQsowyoiF6UgXBEr7eFCWYfXuZDvRxP9zEh1Kwq3TLqDQMbkbaRpSnoC28oWvjLeshoQz1StZ9YHM1EpcJ')
+    assert.equal(hdnode.publicExtendedKey(), 'xpub661MyMwAqRbcGout4B6s29b6gGQsowyoiF6UgXBEr7eFCWYfXuZDvRxP9zEh1Kwq3TLqDQMbkbaRpSnoC28oWvjLeshoQz1StZ9YHM1EpcJ')
+    assert.throws(function () {
+      hdnode.privateExtendedKey()
+    })
+  })
+  it('should work with private', function () {
+    var hdnode = HDKey.fromExtendedKey('xprv9s21ZrQH143K4KqQx9Zrf1eN8EaPQVFxM2Ast8mdHn7GKiDWzNEyNdduJhWXToy8MpkGcKjxeFWd8oBSvsz4PCYamxR7TX49pSpp3bmHVAY')
+    assert.equal(hdnode.publicExtendedKey(), 'xpub661MyMwAqRbcGout4B6s29b6gGQsowyoiF6UgXBEr7eFCWYfXuZDvRxP9zEh1Kwq3TLqDQMbkbaRpSnoC28oWvjLeshoQz1StZ9YHM1EpcJ')
+    assert.equal(hdnode.privateExtendedKey(), 'xprv9s21ZrQH143K4KqQx9Zrf1eN8EaPQVFxM2Ast8mdHn7GKiDWzNEyNdduJhWXToy8MpkGcKjxeFWd8oBSvsz4PCYamxR7TX49pSpp3bmHVAY')
+  })
+})
+
+describe('.deriveChild()', function () {
+  it('should work', function () {
+    var hdnode = fixturehd.deriveChild(1)
+    assert.equal(hdnode.privateExtendedKey(), 'xprv9vYSvrg3eR5FaKbQE4Ao2vHdyvfFL27aWMyH6X818mKWMsqqQZAN6HmRqYDGDPLArzaqbLExRsxFwtx2B2X2QKkC9uoKsiBNi22tLPKZHNS')
+  })
+})
+
+describe('.derivePath()', function () {
+  it('should work with m', function () {
+    var hdnode = fixturehd.derivePath('m')
+    assert.equal(hdnode.privateExtendedKey(), 'xprv9s21ZrQH143K4KqQx9Zrf1eN8EaPQVFxM2Ast8mdHn7GKiDWzNEyNdduJhWXToy8MpkGcKjxeFWd8oBSvsz4PCYamxR7TX49pSpp3bmHVAY')
+  })
+  it('should work with m/44\'/0\'/0/1', function () {
+    var hdnode = fixturehd.derivePath('m/44\'/0\'/0/1')
+    assert.equal(hdnode.privateExtendedKey(), 'xprvA1ErCzsuXhpB8iDTsbmgpkA2P8ggu97hMZbAXTZCdGYeaUrDhyR8fEw47BNEgLExsWCVzFYuGyeDZJLiFJ9kwBzGojQ6NB718tjVJrVBSrG')
+  })
+})
+
+describe('.getWallet()', function () {
+  it('should work', function () {
+    assert.equal(fixturehd.getWallet().getPrivateKeyString(), '0x26cc9417b89cd77c4acdbe2e3cd286070a015d8e380f9cd1244ae103b7d89d81')
+    assert.equal(fixturehd.getWallet().getPublicKeyString(),
+      '0x0639797f6cc72aea0f3d309730844a9e67d9f1866e55845c5f7e0ab48402973defa5cb69df462bcc6d73c31e1c663c225650e80ef14a507b203f2a12aea55bc1')
+  })
+  it('should work with public nodes', function () {
+    var hdnode = HDKey.fromExtendedKey('xpub661MyMwAqRbcGout4B6s29b6gGQsowyoiF6UgXBEr7eFCWYfXuZDvRxP9zEh1Kwq3TLqDQMbkbaRpSnoC28oWvjLeshoQz1StZ9YHM1EpcJ')
+    assert.throws(function () {
+      hdnode.getWallet().getPrivateKeyString()
+    })
+    assert.equal(hdnode.getWallet().getPublicKeyString(), '0x030639797f6cc72aea0f3d309730844a9e67d9f1866e55845c5f7e0ab48402973d')
+  })
+})
diff --git a/test/index.js b/test/index.js
index b52b93d..19e3583 100644
--- a/test/index.js
+++ b/test/index.js
@@ -87,7 +87,6 @@ describe('.fromExtendedPublicKey()', function () {
   })
 })
 
-
 describe('.generate()', function () {
   it('should generate an account', function () {
     assert.equal(Wallet.generate().getPrivateKey().length, 32)