diff --git a/include/boost/graph/property_maps/null_property_map.hpp b/include/boost/graph/property_maps/null_property_map.hpp
index 2d30eea8..f6273481 100644
--- a/include/boost/graph/property_maps/null_property_map.hpp
+++ b/include/boost/graph/property_maps/null_property_map.hpp
@@ -7,7 +7,10 @@
 #ifndef BOOST_GRAPH_NULL_PROPERTY_HPP
 #define BOOST_GRAPH_NULL_PROPERTY_HPP
 
-#include <boost/property_map.hpp>
+#include <boost/property_map/property_map.hpp>
+
+// TODO: This should really be part of the property maps library rather than
+// the Boost.Graph library.
 
 namespace boost
 {