diff --git a/CMakeLists.txt b/CMakeLists.txt
index 53585ccbb..1b3dbeb01 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -89,6 +89,10 @@ OPTION ( BUILD_DOCS
    OFF
 )
 
+if (WIN32)
+    add_definitions( -DWIN32_LEAN_AND_MEAN )
+endif()
+
 IF(MSVC)
   set (CMAKE_PREFIX_PATH "D:\\libs\\devil")
   OPTION( ASSIMP_INSTALL_PDB