diff --git a/TTreeValidation.cc b/TTreeValidation.cc
index acfad654..a41d9203 100644
--- a/TTreeValidation.cc
+++ b/TTreeValidation.cc
@@ -1,6 +1,7 @@
 #include "TTreeValidation.h"
 #include "Event.h"
 #include "Config.h"
+#include "mkFit/IterationConfig.h"
 
 #ifndef NO_ROOT