diff --git a/src/misc/misc_time.c b/src/misc/misc_time.c
index 7a294a838..5c52b6619 100644
--- a/src/misc/misc_time.c
+++ b/src/misc/misc_time.c
@@ -9,9 +9,20 @@ Copyright 1990 Regents of the University of California.  All rights reserved.
 #include "ngspice/ngspice.h"
 #include <string.h>
 
+#if defined(HAS_WINGUI) || defined(__MINGW32__) || defined(_MSC_VER)
 #ifdef HAVE_QUERYPERFORMANCECOUNTER
+#define WIN32_LEAN_AND_MEAN
+ /*
+  * The ngspice.h file included above defines BOOLEAN (via bool.h) and this
+  * clashes with the definition obtained from windows.h (via winnt.h).
+  * However, BOOLEAN is not used by this file so we can work round this problem
+  * by undefining BOOLEAN before including windows.h
+  * SJB - April 2005
+  */
+#undef BOOLEAN
 #include <windows.h>
 #endif
+#endif
 
 #include "misc_time.h"