diff --git a/lib/mixins.js b/lib/mixins.js
new file mode 100644
index 00000000..d16d6561
--- /dev/null
+++ b/lib/mixins.js
@@ -0,0 +1,67 @@
+var debug = require('debug')('loopback:mixin');
+var assert = require('assert');
+var DefaultModelBaseClass = require('./model.js');
+
+function isModelClass(cls) {
+  if (!cls) {
+    return false;
+  }
+  return cls.prototype instanceof DefaultModelBaseClass;
+}
+
+module.exports = MixinProvider;
+
+function MixinProvider(modelBuilder) {
+  this.modelBuilder = modelBuilder;
+  this.mixins = {};
+}
+
+/**
+ * Apply named mixin to the model class
+ * @param {Model} modelClass
+ * @param {String} name
+ * @param {Object} options
+ */
+MixinProvider.prototype.applyMixin = function applyMixin(modelClass, name, options) {
+  var fn = this.mixins[name];
+  if (typeof fn === 'function') {
+    if (modelClass.dataSource) {
+      fn(modelClass, options || {});
+    } else {
+      modelClass.once('dataSourceAttached', function() {
+        fn(modelClass, options || {});
+      });
+    }
+  } else {
+    // Try model name
+    var model = this.modelBuilder.getModel(name);
+    if(model) {
+      debug('Mixin is resolved to a model: %s', name);
+      modelClass.mixin(model, options);
+    } else {
+      debug('Invalid mixin: %s', name);
+    }
+  }
+};
+
+/**
+ * Define a mixin with name
+ * @param {String} name Name of the mixin
+ * @param {*) mixin The mixin function or a model
+ */
+MixinProvider.prototype.define = function defineMixin(name, mixin) {
+  assert(typeof mixin === 'function', 'The mixin must be a function or model class');
+  if (this.mixins[name]) {
+    debug('Duplicate mixin: %s', name);
+  } else {
+    debug('Defining mixin: %s', name);
+  }
+  if (isModelClass(mixin)) {
+    this.mixins[name] = function (Model, options) {
+      Model.mixin(mixin, options);
+    };
+  } else if (typeof mixin === 'function') {
+    this.mixins[name] = mixin;
+  }
+};
+
diff --git a/lib/model-builder.js b/lib/model-builder.js
index aa052dea..73936be5 100644
--- a/lib/model-builder.js
+++ b/lib/model-builder.js
@@ -10,6 +10,7 @@ var DefaultModelBaseClass = require('./model.js');
 var List = require('./list.js');
 var ModelDefinition = require('./model-definition.js');
 var mergeSettings = require('./utils').mergeSettings;
+var MixinProvider = require('./mixins');
 
 // Set up types
 require('./types')(ModelBuilder);
@@ -37,6 +38,7 @@ function ModelBuilder() {
   // create blank models pool
   this.models = {};
   this.definitions = {};
+  this.mixins = new MixinProvider(this);
   this.defaultModelBaseClass = DefaultModelBaseClass;
 }
 
@@ -188,7 +190,7 @@ ModelBuilder.prototype.define = function defineClass(className, properties, sett
 
   // Add metadata to the ModelClass
   hiddenProperty(ModelClass, 'modelBuilder', modelBuilder);
-  hiddenProperty(ModelClass, 'dataSource', modelBuilder); // Keep for back-compatibility
+  hiddenProperty(ModelClass, 'dataSource', null); // Keep for back-compatibility
   hiddenProperty(ModelClass, 'pluralModelName', pluralName);
   hiddenProperty(ModelClass, 'relations', {});
   hiddenProperty(ModelClass, 'http', { path: '/' + pathName });
@@ -428,6 +430,20 @@ ModelBuilder.prototype.define = function defineClass(className, properties, sett
     ModelClass.registerProperty(propertyName);
   }
 
+  var mixinSettings = settings.mixins || {};
+  keys = Object.keys(mixinSettings);
+  size = keys.length;
+  for (i = 0; i < size; i++) {
+    var name = keys[i];
+    var mixin = mixinSettings[name];
+    if (mixin === true) {
+      mixin = {};
+    }
+    if (typeof mixin === 'object') {
+      modelBuilder.mixins.applyMixin(ModelClass, name, mixin);
+    }
+  }
+  
   ModelClass.emit('defined', ModelClass);
 
   return ModelClass;
diff --git a/lib/model.js b/lib/model.js
index 51a59397..b1c28a99 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -201,7 +201,11 @@ ModelBaseClass.prototype._initProperties = function (data, options) {
  * @param {Object} params Various property configuration
  */
 ModelBaseClass.defineProperty = function (prop, params) {
-  this.dataSource.defineProperty(this.modelName, prop, params);
+  if(this.dataSource) {
+    this.dataSource.defineProperty(this.modelName, prop, params);
+  } else {
+    this.modelBuilder.defineProperty(this.modelName, prop, params);
+  }
 };
 
 ModelBaseClass.getPropertyType = function (propName) {
@@ -387,7 +391,20 @@ ModelBaseClass.prototype.inspect = function () {
 };
 
 ModelBaseClass.mixin = function (anotherClass, options) {
-  return jutil.mixin(this, anotherClass, options);
+  if (typeof anotherClass === 'string') {
+    this.modelBuilder.mixins.applyMixin(this, anotherClass, options);
+  } else {
+    if (anotherClass.prototype instanceof ModelBaseClass) {
+      var props = anotherClass.definition.properties;
+      for (var i in props) {
+        if (this.definition.properties[i]) {
+          continue;
+        }
+        this.defineProperty(i, props[i]);
+      }
+    }
+    return jutil.mixin(this, anotherClass, options);
+  }
 };
 
 ModelBaseClass.prototype.getDataSource = function () {
diff --git a/test/mixins.test.js b/test/mixins.test.js
new file mode 100644
index 00000000..f1dacf9d
--- /dev/null
+++ b/test/mixins.test.js
@@ -0,0 +1,91 @@
+// This test written in mocha+should.js
+var should = require('./init.js');
+
+var jdb = require('../');
+var ModelBuilder = jdb.ModelBuilder;
+var DataSource = jdb.DataSource;
+var Memory = require('../lib/connectors/memory');
+
+var modelBuilder = new ModelBuilder();
+var mixins = modelBuilder.mixins;
+
+function timestamps(Model, options) {
+
+  Model.defineProperty('createdAt', { type: Date });
+  Model.defineProperty('updatedAt', { type: Date });
+
+  var originalBeforeSave = Model.beforeSave;
+  Model.beforeSave = function(next, data) {
+    Model.applyTimestamps(data, this.isNewRecord());
+    if (data.createdAt) {
+      this.createdAt = data.createdAt;
+    }
+    if (data.updatedAt) {
+      this.updatedAt = data.updatedAt;
+    }
+    if (originalBeforeSave) {
+      originalBeforeSave.apply(this, arguments);
+    } else {
+      next();
+    }
+  };
+
+  Model.applyTimestamps = function(data, creation) {
+    data.updatedAt = new Date();
+    if (creation) {
+      data.createdAt = data.updatedAt;
+    }
+  };
+}
+
+mixins.define('TimeStamp', timestamps);
+
+describe('Model class', function () {
+  
+  it('should define a mixin', function() {
+    mixins.define('Example', function(Model, options) {
+      Model.prototype.example = function() {
+        return options;
+      };
+    });
+  });
+  
+  it('should apply a mixin class', function() {
+    var Address = modelBuilder.define('Address', {
+      street: { type: 'string', required: true },
+      city: { type: 'string', required: true }
+    });
+
+    var memory = new DataSource('mem', {connector: Memory}, modelBuilder);
+    var Item = memory.createModel('Item', { name: 'string' }, {
+      mixins: { TimeStamp: true, demo: true, Address: true }
+    });
+
+    var properties = Item.definition.properties;
+    
+    properties.street.should.eql({ type: String, required: true });
+    properties.city.should.eql({ type: String, required: true });
+  });
+  
+  it('should apply mixins', function(done) {
+    var memory = new DataSource('mem', {connector: Memory}, modelBuilder);
+    var Item = memory.createModel('Item', { name: 'string' }, {
+      mixins: { TimeStamp: true, demo: { ok: true } }
+    });
+    
+    Item.mixin('Example', { foo: 'bar' });
+    Item.mixin('other');
+    
+    var properties = Item.definition.properties;
+    properties.createdAt.should.eql({ type: Date });
+    properties.updatedAt.should.eql({ type: Date });
+    
+    Item.create({ name: 'Item 1' }, function(err, inst) {
+      inst.createdAt.should.be.a.date;
+      inst.updatedAt.should.be.a.date;
+      inst.example().should.eql({ foo: 'bar' });
+      done();
+    });
+  });
+  
+});