diff --git a/tools/run-unit-tests.sh b/tools/run-unit-tests.sh
new file mode 100755
index 00000000..feab07f9
--- /dev/null
+++ b/tools/run-unit-tests.sh
@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+# Script for passing regex filtering of unit tests to py.test conditionally.
+# Needed because tox currently doesn't support conditional logic like this.
+
+posargs=$@
+if [ ${#posargs} -ge 1 ]; then
+    py.test -vvv -s --ignore=hapi -k $1
+else
+    py.test -vvv -s --ignore=hapi
+fi
+TEST_STATUS=$?
+set -e
+
+exit $TEST_STATUS
diff --git a/tox.ini b/tox.ini
index de4efeb3..e1977697 100644
--- a/tox.ini
+++ b/tox.ini
@@ -17,7 +17,7 @@ whitelist_externals = find
 commands =
   find . -type f -name "*.pyc" -delete
   python -V
-  py.test -vvv -s --ignore=hapi {posargs}
+  {toxinidir}/tools/run-unit-tests.sh {posargs}
 
 [testenv:docs]
 commands =