diff --git a/include/ur_client_library/ur/datatypes.h b/include/ur_client_library/ur/datatypes.h
index 19f8b5d5..a928e0fc 100644
--- a/include/ur_client_library/ur/datatypes.h
+++ b/include/ur_client_library/ur/datatypes.h
@@ -26,6 +26,7 @@
  *
  */
 //----------------------------------------------------------------------
+#pragma once
 
 #include <ur_client_library/types.h>