diff --git a/README b/README
index 46674a119..6ac539fee 100644
--- a/README
+++ b/README
@@ -9,11 +9,16 @@ Clutter currently requires:
   • GLib >= 2.16.0
   • Cairo >= 1.6
   • PangoCairo >= 1.20
-  • OpenGL >= 1.2, OpenGL ES 1.1 or OpenGL ES 2.0
+  • OpenGL >= 1.3 or 1.2+multitexturing, OpenGL ES 1.1 or OpenGL ES 2.0
   • GLX, SDL, WGL or an EGL Implementation
   • JSON-GLib >= 0.8 (optional)
   • GDK-Pixbuf >= 2.0 (optional)
 
+When running the OpenGL flavor, Clutter requires at least version 1.3
+or 1.2 with the multitexturing extension. However to build, Clutter
+requires the latest GL headers which can be obtained from
+www.khronos.org.
+
 If you are building the API reference you will also need:
 
   • GTK-Doc >= 1.11