diff --git a/test-requirements.txt b/test-requirements.txt
index 8410c5c5..4ca9b84a 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -19,6 +19,7 @@ stevedore>=1.17.1 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD
 testresources>=0.2.4 # Apache-2.0/BSD
 testtools>=1.4.0 # MIT
+os-testr>=0.8.0 # Apache-2.0
 python-memcached>=1.56 # PSF
 WebTest>=2.0 # MIT
 
diff --git a/tox.ini b/tox.ini
index a5bc5499..e94c51f8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,11 +11,12 @@ setenv = VIRTUAL_ENV={envdir}
          CLIENT_NAME=keystonemiddleware
          OS_STDOUT_NOCAPTURE=False
          OS_STDERR_NOCAPTURE=False
+         TESTS_DIR=./keystonemiddleware/tests/unit/
 
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
        .[audit_notifications]
-commands = python setup.py testr --testr-args='{posargs}'
+commands = ostestr {posargs}
 
 [testenv:pep8]
 commands =