diff --git a/lib/guard/jasmine-headless-webkit/runner.rb b/lib/guard/jasmine-headless-webkit/runner.rb
index 217e8bc..06a8ac2 100644
--- a/lib/guard/jasmine-headless-webkit/runner.rb
+++ b/lib/guard/jasmine-headless-webkit/runner.rb
@@ -1,4 +1,5 @@
 require 'guard/notifier'
+require 'open3'
 
 module Guard
   class JasmineHeadlessWebkitRunner