diff --git a/tox.ini b/tox.ini
index b722985..6d6b962 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py27,pep8
+envlist = py27,py34,py35,pep8
 
 [testenv]
 usedevelop = True