diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 79defabadeb..52884744535 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -19,6 +19,7 @@
 /// <reference path='external\mocha.d.ts'/>
 /// <reference path='external\chai.d.ts'/>
 /// <reference path='sourceMapRecorder.ts'/>
+/// <reference path='runnerbase.ts'/>
 
 declare var require: any;
 declare var process: any;