diff --git a/imgui.h b/imgui.h
index f4f3e6b7..ca5233c5 100644
--- a/imgui.h
+++ b/imgui.h
@@ -685,7 +685,7 @@ struct ImDrawVert
     ImU32   col;
 };
 #else
-// You can change the vertex format layout by defining IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT.
+// You can change the vertex format layout by defining IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT in imconfig.h
 // The code expect ImVec2 pos (8 bytes), ImVec2 uv (8 bytes), ImU32 col (4 bytes), but you can re-order them or add other fields as needed to simplify integration in your engine.
 // The type has to be described by the #define (you can either declare the struct or use a typedef)
 IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT;