diff --git a/ostream.hpp b/ostream.hpp
index ec8c521..f102d54 100644
--- a/ostream.hpp
+++ b/ostream.hpp
@@ -23,7 +23,7 @@
 
 #include <cruft/util/preprocessor.hpp>
 
-#include <ostream>
+#include <iosfwd>
 
 
 ///////////////////////////////////////////////////////////////////////////////