diff --git a/include/osg/Timer b/include/osg/Timer
index 0e3a1e765..f605167e6 100644
--- a/include/osg/Timer
+++ b/include/osg/Timer
@@ -166,6 +166,7 @@ class SG_EXPORT Timer {
   
 #elif defined(__sgi)
 
+    #include <sys/types.h>
     #include <sys/time.h>
 
     namespace osg{