diff --git a/doc/requirements.txt b/doc/requirements.txt
new file mode 100644
index 0000000..eccc937
--- /dev/null
+++ b/doc/requirements.txt
@@ -0,0 +1,2 @@
+sphinx>=2.0.0,!=2.1.0 # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
diff --git a/test-requirements.txt b/test-requirements.txt
index 19f7716..77ff883 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,6 +4,3 @@
 stestr>=2.0.0 # Apache-2.0
 testresources>=2.0.0 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
-
-sphinx>=2.0.0,!=2.1.0 # BSD
-openstackdocstheme>=2.2.1 # Apache-2.0
diff --git a/tox.ini b/tox.ini
index 2a19edf..c379b66 100644
--- a/tox.ini
+++ b/tox.ini
@@ -27,6 +27,8 @@ commands = flake8
 commands = {posargs}
 
 [testenv:docs]
+deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+       -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-build -W -b html doc/source doc/build/html