diff --git a/HACKING.rst b/HACKING.rst
index 4333d2568..84e81af97 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -199,7 +199,10 @@ bug that had no unit test, a new passing unit test should be added. If a
 submitted bug fix does have a unit test, be sure to add a new one that fails
 without the patch and passes with the patch.
 
-All unittest classes must ultimately inherit from testtools.TestCase.
+All unittest classes must ultimately inherit from testtools.TestCase. In the
+Quantum test suite, this should be done by inheriting from
+quantum.tests.base.BaseTestCase.
+
 All setUp and tearDown methods must upcall using the super() method.
 tearDown methods should be avoided and addCleanup calls should be preferred.
 Never manually create tempfiles. Always use the tempfile fixtures from