diff --git a/novaclient/tests/functional/base.py b/novaclient/tests/functional/base.py
index be4c5d74f..58403a078 100644
--- a/novaclient/tests/functional/base.py
+++ b/novaclient/tests/functional/base.py
@@ -258,7 +258,7 @@ class ClientTestBase(testtools.TestCase):
         # something more sensible.
         cli_dir = os.environ.get(
             'OS_NOVACLIENT_EXEC_DIR',
-            os.path.join(os.path.abspath('.'), '.tox/functional/bin'))
+            os.path.join(os.environ['TOX_ENV_DIR'], 'bin'))
 
         self.cli_clients = tempest.lib.cli.base.CLIClient(
             username=user,
diff --git a/tox.ini b/tox.ini
index f444646a0..319a2a81f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -61,7 +61,7 @@ deps =
 commands =
   sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
-[testenv:functional]
+[testenv:functional{,-py38,-py39,-py310,-py311,-py312}]
 passenv = OS_*
 commands =
   stestr --test-path=./novaclient/tests/functional run --concurrency=1 {posargs}