diff --git a/package.json b/package.json
index 4b220ad..ea5e5a3 100644
--- a/package.json
+++ b/package.json
@@ -12,7 +12,7 @@
     "fs-extra": "0.12.0",
     "requirejs": "2.1.11",
     "underscore": "1.6.x",
-    "underscore.string": "2.3.x",
+    "underscore.string": "3.3.x",
     "watch": "~0.11.x",
     "uglify-js": "1.3.5",
     "socket.io": "~1.2",