diff --git a/XWBTool/CmdLineHelpers.h b/XWBTool/CmdLineHelpers.h
index 92e544ca..b3af3ee5 100644
--- a/XWBTool/CmdLineHelpers.h
+++ b/XWBTool/CmdLineHelpers.h
@@ -23,6 +23,10 @@
 #include <set>
 #include <string>
 
+#ifndef TOOL_VERSION
+#error Define TOOL_VERSION before including this header
+#endif
+
 
 namespace Helpers
 {
@@ -162,9 +166,9 @@ namespace Helpers
             }
         }
 
-        if (!*version)
+        if (!*version || wcscmp(version, L"1.0.0.0") == 0)
         {
-            wcscpy_s(version, L"MISSING");
+            swprintf_s(version, L"%03d (library)", TOOL_VERSION);
         }
 
         if (versionOnly)
diff --git a/XWBTool/xwbtool.cpp b/XWBTool/xwbtool.cpp
index 6951fc56..804c6e25 100644
--- a/XWBTool/xwbtool.cpp
+++ b/XWBTool/xwbtool.cpp
@@ -57,6 +57,8 @@
 #include <vector>
 
 #include "WAVFileReader.h"
+
+#define TOOL_VERSION 0
 #include "CmdLineHelpers.h"
 
 using namespace Helpers;