diff --git a/common.h b/common.h
index e7320f32..d10758e1 100644
--- a/common.h
+++ b/common.h
@@ -26,9 +26,19 @@
 #define COMMON_H
 
 /*
- * Statistics counters.
+ * Statistics counters and associated printf formats.
  */
-typedef unsigned long long int counter_type;
+#ifdef USE_64_BIT_COUNTERS
+  typedef unsigned long long int counter_type;
+# ifdef WIN32
+#  define counter_format  "%I64u"
+# else
+#  define counter_format  "%llu"
+# endif
+#else
+  typedef unsigned int counter_type;
+# define counter_format   "%u"
+#endif
 
 /*
  * Time intervals
@@ -43,7 +53,6 @@ typedef int interval_t;
 /*
  * Printf formats for special types
  */
-#define counter_format          "%llu"
 #define ptr_format              "0x%08lx"
 #define time_format             "%lu"
 #define fragment_header_format  "0x%08x"
diff --git a/syshead.h b/syshead.h
index 950af533..f296fe01 100644
--- a/syshead.h
+++ b/syshead.h
@@ -379,6 +379,11 @@ socket_defined (const socket_descriptor_t sd)
   return sd != SOCKET_UNDEFINED;
 }
 
+/*
+ * Should statistics counters be 64 bits?
+ */
+#define USE_64_BIT_COUNTERS
+
 /*
  * Do we have point-to-multipoint capability?
  */