diff --git a/tox.ini b/tox.ini
index 1be13db..e3b103e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,7 +3,7 @@ envlist = clean, py26, py27, py33, py34, docs, coverage
 
 [testenv]
 commands =
-    py.test
+    py.test {posargs}
 deps =
     pytest
     mock
@@ -24,7 +24,7 @@ deps =
     pytest-cov
     {[testenv]deps}
 commands =
-    py.test --cov=ogre
+    py.test --cov=ogre {posargs}
 usedevelop = true
 
 [testenv:coveralls]