diff --git a/src/xcb_auth.c b/src/xcb_auth.c
index 8ebe9a437..9a1e459fc 100644
--- a/src/xcb_auth.c	
+++ b/src/xcb_auth.c
@@ -46,6 +46,9 @@
 #include <X11/Xwindows.h>
 #endif
 #include "xcb_windefs.h"
+#ifdef _MSC_VER
+#include <process.h>
+#endif
 #else
 #include <sys/param.h>
 #include <unistd.h>