diff --git a/Bizware/BizHawk.Bizware.BizwareGL/GuiRenderer.cs b/Bizware/BizHawk.Bizware.BizwareGL/GuiRenderer.cs
index 2ebce1a3ea..6699db6e01 100644
--- a/Bizware/BizHawk.Bizware.BizwareGL/GuiRenderer.cs
+++ b/Bizware/BizHawk.Bizware.BizwareGL/GuiRenderer.cs
@@ -3,6 +3,7 @@
 //why this stupid assert on the blendstate. just set one by default, geeze.
 
 using System;
+using System.Diagnostics;
 using OpenTK;
 using OpenTK.Graphics.OpenGL;