diff --git a/tox.ini b/tox.ini
index 8c06a6429e..fd272b75dd 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,3 +12,4 @@ commands = pep8 --count --repeat --show-source --exclude=.tox setup.py
 [testenv:venv]
 commands = {posargs}
 deps = Sphinx
+       docutils==0.9.1