diff --git a/lib/models/user.js b/lib/models/user.js
index d1bf7e83..357c70f2 100644
--- a/lib/models/user.js
+++ b/lib/models/user.js
@@ -527,10 +527,12 @@ User.setup = function () {
   UserModel.email = require('./email');
   UserModel.accessToken = require('./access-token');
 
-  UserModel.validatesUniquenessOf('email', {message: 'Email already exists'});
+  // email validation regex
   var re = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
 
+  UserModel.validatesUniquenessOf('email', {message: 'Email already exists'});
   UserModel.validatesFormatOf('email', {with: re, message: 'Must provide a valid email'});
+  UserModel.validatesUniquenessOf('username',  {message: 'User already exists'});
 
   return UserModel;
 }
diff --git a/test/user.test.js b/test/user.test.js
index 047ff831..ccfb0c8b 100644
--- a/test/user.test.js
+++ b/test/user.test.js
@@ -109,6 +109,15 @@ describe('User', function(){
         });
       });
     });
+
+    it('Requires a unique username', function(done) {
+      User.create({email: 'a@b.com', username: 'abc', password: 'foobar'}, function () {
+        User.create({email: 'b@b.com', username: 'abc',  password: 'batbaz'}, function (err) {
+          assert(err, 'should error because the username is not unique!');
+          done();
+        });
+      });
+    }); 
     
     it('Requires a password to login with basic auth', function(done) {
       User.create({email: 'b@c.com'}, function (err) {