diff --git a/src/compiler/tsc.ts b/src/compiler/tsc.ts
index d355c49ab29..abefd6e4819 100644
--- a/src/compiler/tsc.ts
+++ b/src/compiler/tsc.ts
@@ -86,13 +86,18 @@ module ts {
     }
 
     function reportDiagnostic(diagnostic: Diagnostic) {
+        var output = "";
+        
         if (diagnostic.file) {
             var loc = diagnostic.file.getLineAndCharacterFromPosition(diagnostic.start);
-            sys.write(diagnostic.file.filename + "(" + loc.line + "," + loc.character + "): " + diagnostic.messageText + sys.newLine);
-        }
-        else {
-            sys.write(diagnostic.messageText + sys.newLine);
+
+            var output = diagnostic.file.filename + "(" + loc.line + "," + loc.character + "): ";
         }
+
+        var category = DiagnosticCategory[diagnostic.category];
+        output += category + " TS" + diagnostic.code + ": " + diagnostic.messageText + sys.newLine;
+
+        sys.write(output);
     }
 
     function reportDiagnostics(diagnostics: Diagnostic[]) {