diff --git a/doc/requirements.txt b/doc/requirements.txt
new file mode 100644
index 0000000000..828aab9ad3
--- /dev/null
+++ b/doc/requirements.txt
@@ -0,0 +1,20 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
+# required to build documentation
+openstackdocstheme>=1.17.0 # Apache-2.0
+sphinx>=1.6.2 # BSD
+reno>=2.5.0 # Apache-2.0
+fixtures>=3.0.0 # Apache-2.0/BSD
+os-api-ref>=1.4.0 # Apache-2.0
+testtools>=2.2.0 # MIT
+WebTest>=2.0.27 # MIT
+mock>=2.0.0 # BSD
+freezegun>=0.3.6 # Apache-2.0
+flake8-docstrings==0.2.1.post1 # MIT
+oslotest>=1.10.0 # Apache-2.0
+oslo.db[fixtures,mysql,postgresql]>=4.27.0 # Apache-2.0
+lxml!=3.7.0,>=3.4.1 # BSD
+pyldap>=2.4.20 # PSF
+ldappool>=2.0.0 # MPL
diff --git a/test-requirements.txt b/test-requirements.txt
index f34041fdec..8fc6bd0a23 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -22,8 +22,7 @@ lxml!=3.7.0,>=3.4.1 # BSD
 # mock object framework
 mock>=2.0.0 # BSD
 oslotest>=1.10.0 # Apache-2.0
-# required to build documentation
-sphinx>=1.6.2 # BSD
+
 os-api-ref>=1.4.0 # Apache-2.0
 # test wsgi apps without starting an http server
 WebTest>=2.0.27 # MIT
@@ -31,10 +30,6 @@ WebTest>=2.0.27 # MIT
 stestr>=1.0.0 # Apache-2.0
 testtools>=2.2.0 # MIT
 
-# For documentation
-openstackdocstheme>=1.17.0 # Apache-2.0
-reno>=2.5.0 # Apache-2.0
-
 tempest>=17.1.0 # Apache-2.0
 
 # Functional tests.
diff --git a/tox.ini b/tox.ini
index 85c609e99f..92f1b41aae 100644
--- a/tox.ini
+++ b/tox.ini
@@ -119,12 +119,14 @@ exclude=.venv,.git,.tox,build,dist,*lib/python*,*egg,tools,vendor,.update-venv,*
 max-complexity=24
 
 [testenv:docs]
+deps = -r{toxinidir}/doc/requirements.txt
 commands=
     bash -c "rm -rf doc/build"
     bash -c "rm -rf doc/source/api"
     python setup.py build_sphinx
 
 [testenv:releasenotes]
+deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:genconfig]