diff --git a/src/frontends/qt4/Dialog.h b/src/frontends/qt4/Dialog.h
index f764164ef1..1bd75673c5 100644
--- a/src/frontends/qt4/Dialog.h
+++ b/src/frontends/qt4/Dialog.h
@@ -14,8 +14,9 @@
 
 #include "FuncCode.h"
 
+#include "support/strfwd.h"
+
 #include <QString>
-#include <string>
 
 class QWidget;