diff --git a/common/models/role-mapping.js b/common/models/role-mapping.js
index 630cbd3c..8dfa5808 100644
--- a/common/models/role-mapping.js
+++ b/common/models/role-mapping.js
@@ -5,6 +5,7 @@
 
 'use strict';
 var loopback = require('../../lib/loopback');
+var utils = require('../../lib/utils');
 
 /**
  * The `RoleMapping` model extends from the built in `loopback.Model` type.
@@ -26,9 +27,9 @@ module.exports = function(RoleMapping) {
   RoleMapping.resolveRelatedModels = function() {
     if (!this.userModel) {
       var reg = this.registry;
-      this.roleModel = reg.getModelByType(loopback.Role);
-      this.userModel = reg.getModelByType(loopback.User);
-      this.applicationModel = reg.getModelByType(loopback.Application);
+      this.roleModel = reg.getModelByType('Role');
+      this.userModel = reg.getModelByType('User');
+      this.applicationModel = reg.getModelByType('Application');
     }
   };
 
@@ -39,6 +40,7 @@ module.exports = function(RoleMapping) {
    * @param {Application} application
    */
   RoleMapping.prototype.application = function(callback) {
+    callback = callback || utils.createPromiseCallback();
     this.constructor.resolveRelatedModels();
 
     if (this.principalType === RoleMapping.APPLICATION) {
@@ -46,9 +48,10 @@ module.exports = function(RoleMapping) {
       applicationModel.findById(this.principalId, callback);
     } else {
       process.nextTick(function() {
-        if (callback) callback(null, null);
+        callback(null, null);
       });
     }
+    return callback.promise;
   };
 
   /**
@@ -58,15 +61,18 @@ module.exports = function(RoleMapping) {
    * @param {User} user
    */
   RoleMapping.prototype.user = function(callback) {
+    callback = callback || utils.createPromiseCallback();
     this.constructor.resolveRelatedModels();
+
     if (this.principalType === RoleMapping.USER) {
       var userModel = this.constructor.userModel;
       userModel.findById(this.principalId, callback);
     } else {
       process.nextTick(function() {
-        if (callback) callback(null, null);
+        callback(null, null);
       });
     }
+    return callback.promise;
   };
 
   /**
@@ -76,6 +82,7 @@ module.exports = function(RoleMapping) {
    * @param {User} childUser
    */
   RoleMapping.prototype.childRole = function(callback) {
+    callback = callback || utils.createPromiseCallback();
     this.constructor.resolveRelatedModels();
 
     if (this.principalType === RoleMapping.ROLE) {
@@ -83,8 +90,9 @@ module.exports = function(RoleMapping) {
       roleModel.findById(this.principalId, callback);
     } else {
       process.nextTick(function() {
-        if (callback) callback(null, null);
+        callback(null, null);
       });
     }
+    return callback.promise;
   };
 };
diff --git a/test/role-mapping.test.js b/test/role-mapping.test.js
new file mode 100644
index 00000000..afc794b0
--- /dev/null
+++ b/test/role-mapping.test.js
@@ -0,0 +1,116 @@
+// Copyright IBM Corp. 2013,2016. All Rights Reserved.
+// Node module: loopback
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+'use strict';
+var expect = require('./helpers/expect');
+var loopback = require('../');
+var Promise = require('bluebird');
+
+describe('role-mapping model', function() {
+  this.timeout(10000);
+
+  var app, oneUser, anApp, aRole;
+  var models = {};
+
+  beforeEach(function() {
+    app = loopback({localRegistry: true, loadBuiltinModels: true});
+    app.dataSource('db', {connector: 'memory'});
+
+    // setup models
+    ['User', 'Role', 'RoleMapping', 'Application'].map(setupModel);
+
+    // create generic instances
+    return Promise.all([
+      models.User.create({
+        username: 'oneUser',
+        email: 'user@email.com',
+        password: 'password',
+      }),
+      models.Application.create({name: 'anApp'}),
+      models.Role.create({name: 'aRole'}),
+    ])
+    .spread(function(u, a, r) {
+      oneUser = u;
+      anApp = a;
+      aRole = r;
+    });
+
+    // helper
+    function setupModel(modelName) {
+      var model = app.registry.getModel(modelName);
+      app.model(model, {dataSource: 'db'});
+      models[modelName] = model;
+    }
+  });
+
+  it('supports .user() with a callback', function(done) {
+    models.RoleMapping.create(
+      {principalType: 'USER', principalId: oneUser.id},
+      function(err, mapping) {
+        if (err) done(err);
+        mapping.user(function(err, user) {
+          if (err) done(err);
+          expect(user.id).to.equal(oneUser.id);
+          done();
+        });
+      });
+  });
+
+  it('supports .user() returning a promise', function() {
+    return models.RoleMapping.create({principalType: 'USER', principalId: oneUser.id})
+      .then(function(mapping) {
+        return mapping.user();
+      })
+      .then(function(user) {
+        expect(user.id).to.equal(oneUser.id);
+      });
+  });
+
+  it('supports .application() with a callback', function(done) {
+    models.RoleMapping.create(
+      {principalType: 'APP', principalId: anApp.id},
+      function(err, mapping) {
+        if (err) done(err);
+        mapping.application(function(err, app) {
+          if (err) done(err);
+          expect(app.id).to.equal(anApp.id);
+          done();
+        });
+      });
+  });
+
+  it('supports .application() returning a promise', function() {
+    return models.RoleMapping.create({principalType: 'APP', principalId: anApp.id})
+      .then(function(mapping) {
+        return mapping.application();
+      })
+      .then(function(app) {
+        expect(app.id).to.equal(anApp.id);
+      });
+  });
+
+  it('supports .childRole() with a callback', function(done) {
+    models.RoleMapping.create(
+      {principalType: 'ROLE', principalId: aRole.id},
+      function(err, mapping) {
+        if (err) done(err);
+        mapping.childRole(function(err, role) {
+          if (err) done(err);
+          expect(role.id).to.equal(aRole.id);
+          done();
+        });
+      });
+  });
+
+  it('supports .childRole() returning a promise', function() {
+    return models.RoleMapping.create({principalType: 'ROLE', principalId: aRole.id})
+      .then(function(mapping) {
+        return mapping.childRole();
+      })
+      .then(function(role) {
+        expect(role.id).to.equal(aRole.id);
+      });
+  });
+});