diff --git a/tox.ini b/tox.ini
index ff0bd9a..3a014bc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,8 @@
 [tox]
-minversion = 2.0
-envlist = py35,py27,pypy,pep8
+minversion = 3.1.1
+envlist = py35,py36,pypy,pep8
 skipsdist = True
+ignore_basepython_conflict = True
 
 [testenv]
 usedevelop = True
@@ -11,30 +12,25 @@
    PYTHONWARNINGS=default::DeprecationWarning
 deps = -r{toxinidir}/test-requirements.txt
 commands = python setup.py test --slowest --testr-args='{posargs}'
+basepython = python3
 
 [testenv:pep8]
-basepython = python3
 commands = flake8 {posargs}
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
 [testenv:cover]
-basepython = python3
 commands = python setup.py test --coverage --testr-args='{posargs}'
 
 [testenv:docs]
-basepython = python3
 commands = sphinx-build -W -b html -d doc/buld/doctrees doc/source doc/build/html
 
 [testenv:releasenotes]
-basepython = python3
 commands =
   sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:debug]
-basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [flake8]