diff --git a/rtengine/improcfun.h b/rtengine/improcfun.h
index 4e40063b9..9de16db00 100644
--- a/rtengine/improcfun.h
+++ b/rtengine/improcfun.h
@@ -25,7 +25,7 @@
 #include "jaggedarray.h"
 #include "pipettebuffer.h"
 #include "shmap.h"
-
+#include "array2D.h"
 template<typename T>
 class LUT;