diff --git a/README.md b/README.md
index a1e5aee24..c4a4097bf 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,7 @@ List of Definitions
 * [EaselJS](http://www.createjs.com/#!/EaselJS) (by [Pedro Ferreira](https://bitbucket.org/drk4))
 * [ember.js](http://emberjs.com/) (by [Boris Yankov](https://github.com/borisyankov))
 * [EpicEditor](http://epiceditor.com/) (by [Boris Yankov](https://github.com/borisyankov))
+* [expect.js](https://github.com/LearnBoost/expect.js) (by [Teppei Sato](https://github.com/teppeis))
 * [Express](http://expressjs.com/) (by [Boris Yankov](https://github.com/borisyankov))
 * [Fabric.js](http://fabricjs.com/) (by [Oliver Klemencic](https://github.com/oklemencic/))
 * [Fancybox](http://fancybox.net/) (by [Boris Yankov](https://github.com/borisyankov))