diff --git a/README.md b/README.md
index e6b9e06..aabe147 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@ Dependencies:
 - Python 2.7.x
 - [PyHook][pyhook] (if using windows, [PyxHook][pyxhook] on linux)
 - [Pygame][pygame]
+- Make sure you have xlib installed
 
 When you've made sure your `python` is version 2.7.x,