diff --git a/Modules/FindFLTK.cmake b/Modules/FindFLTK.cmake
index 4fd5269a0..56b4c36eb 100644
--- a/Modules/FindFLTK.cmake
+++ b/Modules/FindFLTK.cmake
@@ -50,7 +50,7 @@ IF(UNIX)
 ENDIF(UNIX)
 
 IF(APPLE)
-  SET( FLTK_PLATFORM_DEPENDENT_LIBS  -framework Carbon -framework Cocoa -framework ApplicationServices -lz )
+  SET( FLTK_PLATFORM_DEPENDENT_LIBS  "-framework Carbon -framework Cocoa -framework ApplicationServices -lz")
 ENDIF(APPLE)
 
 # Make sure that the FLTK include path has been set