diff --git a/backstack.js b/backstack.js
index 4eee799..7a8f15b 100644
--- a/backstack.js
+++ b/backstack.js
@@ -22,7 +22,7 @@
     // Set up BackStack appropriately for the environment.
     if (typeof define === 'function' && define.amd) {
         // AMD
-        define(['jquery', 'underscore', 'Backbone'], factory);
+        define(['jquery', 'underscore', 'backbone'], factory);
     } else {
         // Browser globals
         root.BackStack = factory((root.jQuery || root.Zepto || root.ender), root._, root.Backbone);
@@ -1114,4 +1114,4 @@ define('effects/NoEffect',['effects/Effect'], function (Effect) {
         SlideEffect : require('effects/SlideEffect'),
         FadeEffect : require('effects/FadeEffect')
     };
-}));
\ No newline at end of file
+}));