diff --git a/include/X11/Xwindows.h b/include/X11/Xwindows.h
index 900257928..666ee6515 100644
--- a/include/X11/Xwindows.h	
+++ b/include/X11/Xwindows.h
@@ -41,6 +41,11 @@ The Open Group.
  * do as it's no help at all to X11 clients which also need to use the
  * Win32 API)
  */
+#pragma once
+
+#ifndef _X11_XWINDOWS_H_
+#define _X11_XWINDOWS_H_
+
 #undef _XFree86Server
 #ifdef XFree86Server
 # define _XFree86Server
@@ -130,3 +135,4 @@ typedef int Status;
 # undef _XFree86Server
 #endif
 
+#endif
diff --git a/include/X11/Xwinsock.h b/include/X11/Xwinsock.h
index 92e0d2a33..1e3e8671b 100644
--- a/include/X11/Xwinsock.h	
+++ b/include/X11/Xwinsock.h
@@ -32,6 +32,10 @@ The Open Group.
  * Conflicts come from the fact that including winsock.h actually pulls
  * in the whole Windows API...
  */
+#pragma once
+
+#ifndef _X11_XWINSOCK_H_
+#define _X11_XWINSOCK_H_
 
 #undef _XFree86Server
 #ifdef XFree86Server
@@ -100,3 +104,4 @@ typedef int Status;
 # undef _XFree86Server
 #endif
 
+#endif