diff --git a/src/osg/GraphicsContext.cpp b/src/osg/GraphicsContext.cpp
index 135b50f3e..29f3ed015 100644
--- a/src/osg/GraphicsContext.cpp
+++ b/src/osg/GraphicsContext.cpp
@@ -28,6 +28,7 @@
 
 #include <map>
 #include <sstream>
+#include <algorithm>
 
 using namespace osg;