diff --git a/lib/networks.js b/lib/networks.js
index 7994b38..e3280c4 100644
--- a/lib/networks.js
+++ b/lib/networks.js
@@ -2,6 +2,8 @@
 var _ = require('lodash');
 
 var BufferUtil = require('./util/buffer');
+var networks = [];
+var networkMaps = {};
 
 /**
  * A network is merely a map containing values that correspond to version
@@ -15,79 +17,19 @@ Network.prototype.toString = function toString() {
   return this.name;
 };
 
-/**
- * @instance
- * @member Network#livenet
- */
-var livenet = new Network();
-_.extend(livenet, {
-  name: 'livenet',
-  alias: 'mainnet',
-  pubkeyhash: 0x00,
-  privatekey: 0x80,
-  scripthash: 0x05,
-  xpubkey:  0x0488b21e,
-  xprivkey: 0x0488ade4,
-  networkMagic: BufferUtil.integerAsBuffer(0xf9beb4d9),
-  port: 8333,
-  dnsSeeds: [
-    'seed.bitcoin.sipa.be',
-    'dnsseed.bluematt.me',
-    'dnsseed.bitcoin.dashjr.org',
-    'seed.bitcoinstats.com',
-    'seed.bitnodes.io',
-    'bitseed.xf2.org'
-  ]
-});
-
-/**
- * @instance
- * @member Network#testnet
- */
-var testnet = new Network();
-_.extend(testnet, {
-  name: 'testnet',
-  alias: 'testnet',
-  pubkeyhash: 0x6f,
-  privatekey: 0xef,
-  scripthash: 0xc4,
-  xpubkey: 0x043587cf,
-  xprivkey: 0x04358394,
-  networkMagic: BufferUtil.integerAsBuffer(0x0b110907),
-  port: 18333,
-  dnsSeeds: [
-    'testnet-seed.bitcoin.petertodd.org',
-    'testnet-seed.bluematt.me'
-  ],
-});
-
-var networkMaps = {};
-
-_.each(_.values(livenet), function(value) {
-  if (!_.isObject(value)) {
-    networkMaps[value] = livenet;
-  }
-});
-_.each(_.values(testnet), function(value) {
-  if (!_.isObject(value)) {
-    networkMaps[value] = testnet;
-  }
-});
-
 /**
  * @function
- * @member Network#getNetwork
+ * @member Networks#get
  * Retrieves the network associated with a magic number or string.
  * @param {string|number|Network} arg
  * @param {string} key - if set, only check if the magic number associated with this name matches
  * @return Network
  */
 function getNetwork(arg, key) {
-  if (arg === livenet || arg === testnet) {
+  if (~networks.indexOf(arg)) {
     return arg;
   }
   if (key) {
-    var networks = [livenet, testnet];
     for (var index in networks) {
       if (networks[index][key] === arg) {
         return networks[index];
@@ -99,9 +41,104 @@ function getNetwork(arg, key) {
 }
 
 /**
- * @namespace Network
+ * @function
+ * @member Networks#add
+ * Will add a custom Network
+ * @param {Object} data
+ * @param {String} data.name - The name of the network
+ * @param {String} data.alias - The aliased name of the network
+ * @param {Number} data.pubkeyhash - The publickey hash prefix
+ * @param {Number} data.privatekey - The privatekey prefix
+ * @param {Number} data.scripthash - The scripthash prefix
+ * @param {Number} data.xpubkey - The extended public key magic
+ * @param {Number} data.xprivkey - The extended private key magic
+ * @param {Number} data.networkMagic - The network magic number
+ * @param {Number} data.port - The network port
+ * @param {Array}  data.dnsSeeds - An array of dns seeds
+ * @return Network
+ */
+function addNetwork(data) {
+
+  var network = new Network();
+
+  _.extend(network, {
+    name: data.name,
+    alias: data.alias,
+    pubkeyhash: data.pubkeyhash,
+    privatekey: data.privatekey,
+    scripthash: data.scripthash,
+    xpubkey: data.xpubkey,
+    xprivkey: data.xprivkey,
+    networkMagic: BufferUtil.integerAsBuffer(data.networkMagic),
+    port: data.port,
+    dnsSeeds: data.dnsSeeds
+  });
+
+  _.each(_.values(network), function(value) {
+    if (!_.isObject(value)) {
+      networkMaps[value] = network;
+    }
+  });
+
+  networks.push(network);
+
+  return network;
+
+}
+
+addNetwork({
+  name: 'livenet',
+  alias: 'mainnet',
+  pubkeyhash: 0x00,
+  privatekey: 0x80,
+  scripthash: 0x05,
+  xpubkey:  0x0488b21e,
+  xprivkey: 0x0488ade4,
+  networkMagic: 0xf9beb4d9,
+  port: 8333,
+  dnsSeeds: [
+    'seed.bitcoin.sipa.be',
+    'dnsseed.bluematt.me',
+    'dnsseed.bitcoin.dashjr.org',
+    'seed.bitcoinstats.com',
+    'seed.bitnodes.io',
+    'bitseed.xf2.org'
+  ]
+});
+
+addNetwork({
+  name: 'testnet',
+  alias: 'testnet',
+  pubkeyhash: 0x6f,
+  privatekey: 0xef,
+  scripthash: 0xc4,
+  xpubkey: 0x043587cf,
+  xprivkey: 0x04358394,
+  networkMagic: 0x0b110907,
+  port: 18333,
+  dnsSeeds: [
+    'testnet-seed.bitcoin.petertodd.org',
+    'testnet-seed.bluematt.me'
+  ],
+});
+
+/**
+* @instance
+* @member Networks#livenet
+*/
+var livenet = getNetwork('livenet');
+
+/**
+* @instance
+* @member Networks#testnet
+*/
+var testnet = getNetwork('testnet');
+
+/**
+ * @namespace Networks
  */
 module.exports = {
+  add: addNetwork,
   defaultNetwork: livenet,
   livenet: livenet,
   mainnet: livenet,
diff --git a/test/networks.js b/test/networks.js
index a542c7b..ddcd07a 100644
--- a/test/networks.js
+++ b/test/networks.js
@@ -13,6 +13,34 @@ describe('Networks', function() {
     should.exist(networks.defaultNetwork);
   });
 
+  it('should be able to define a custom Network', function() {
+    var custom = {
+      name: 'customnet',
+      alias: 'mynet',
+      pubkeyhash: 0x10,
+      privatekey: 0x90,
+      scripthash: 0x08,
+      xpubkey:  0x0278b20e,
+      xprivkey: 0x0278ade4,
+      networkMagic: 0xe7beb4d4,
+      port: 20001,
+      dnsSeeds: [
+        'localhost',
+        'mynet.localhost'
+      ]
+    };
+    networks.add(custom);
+    var customnet = networks.get('customnet');
+    for (var key in custom) {
+      if (key !== 'networkMagic') {
+        customnet[key].should.equal(custom[key]);
+      } else {
+        var expected = new Buffer('e7beb4d4', 'hex');
+        customnet[key].should.deep.equal(expected);
+      }
+    }
+  });
+
   var constants = ['name', 'alias', 'pubkeyhash', 'scripthash', 'xpubkey', 'xprivkey'];
 
   constants.forEach(function(key){