diff --git a/simgear/scene/model/SGReaderWriterXMLOptions.hxx b/simgear/scene/model/SGReaderWriterXMLOptions.hxx
index b9f46542..17532aee 100644
--- a/simgear/scene/model/SGReaderWriterXMLOptions.hxx
+++ b/simgear/scene/model/SGReaderWriterXMLOptions.hxx
@@ -19,6 +19,7 @@
 #define SGREADERWRITERXMLOPTIONS_HXX 1
 
 #include <osgDB/ReaderWriter>
+#include <simgear/scene/model/modellib.hxx>
 #include <simgear/props/props.hxx>
 
 class SGPropertyNode;