diff --git a/include/mapnik/layer.hpp b/include/mapnik/layer.hpp
index 049724b46..0de81ffa1 100644
--- a/include/mapnik/layer.hpp
+++ b/include/mapnik/layer.hpp
@@ -29,6 +29,7 @@
 
 // stl
 #include <vector>
+#include <memory>
 
 namespace mapnik
 {