diff --git a/tox.ini b/tox.ini
index 58f7c63..4aa599d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,13 +1,8 @@
 [tox]
 minversion = 3.18.0
 envlist = py3,functional,pep8
-# Automatic envs (pyXX) will use the python version appropriate to that
-# env and ignore basepython inherited from [testenv]. That's what we
-# want, and we don't need to be warned about it.
-ignore_basepython_conflict = true
 
 [testenv]
-basepython = python3
 usedevelop = true
 allowlist_externals =
   rm
@@ -25,9 +20,23 @@ commands = stestr run {posargs}
 [testenv:functional]
 description =
   Run functional tests using python3.
+# As osc-placement functional tests import the PlacementFixture from the placement
+# repository these tests are, by default, set up to run with openstack-placement
+# from pypi. In the gate, Zuul will use the installed version of placement (stable
+# branch version on stable gate run) OR the version of placement the Depends-On in
+# the commit message suggests. If you want to run the tests with latest master from
+# the placement repo, modify the dep line to point at master, example:
+# deps =
+#   {[testenv]deps}
+#   git+https://opendev.org/openstack/placement#egg=openstack-placement
+# If you want to run the test locally with an un-merged placement change,
+# modify the dep line to point to your dependency or pip install placement
+# into the appropriate tox virtualenv.
+# NOTE: We express the requirement here instead of test-requirements
+# because we do not want placement present during unit tests.
 deps =
   {[testenv]deps}
-  git+https://opendev.org/openstack/placement.git#egg=openstack-placement
+  openstack-placement>=1.0.0
 commands = stestr --test-path=./osc_placement/tests/functional run {posargs}
 
 [testenv:functional-py38]