diff --git a/zipline/core/devsimulator.py b/zipline/core/devsimulator.py
index 6bc76815..c28d0e72 100644
--- a/zipline/core/devsimulator.py
+++ b/zipline/core/devsimulator.py
@@ -4,7 +4,6 @@ See :py:method""
 """
 
 import logbook
-import threading
 
 log = logbook.Logger('Dev Simulator')