diff --git a/libraries/AC_CustomControl/AC_CustomControl.cpp b/libraries/AC_CustomControl/AC_CustomControl.cpp
index 147dedd198b..b8c7a58eaa3 100644
--- a/libraries/AC_CustomControl/AC_CustomControl.cpp
+++ b/libraries/AC_CustomControl/AC_CustomControl.cpp
@@ -8,6 +8,7 @@
 #include "AC_CustomControl_Backend.h"
 // #include "AC_CustomControl_Empty.h"
 #include "AC_CustomControl_PID.h"
+#include <GCS_MAVLink/GCS.h>
 
 // table of user settable parameters
 const AP_Param::GroupInfo AC_CustomControl::var_info[] = {