diff --git a/doc/requirements.txt b/doc/requirements.txt
new file mode 100644
index 00000000..ba6a41d2
--- /dev/null
+++ b/doc/requirements.txt
@@ -0,0 +1,5 @@
+# Documentation
+sphinx!=1.6.6,>=1.6.2 # BSD
+openstackdocstheme>=1.18.1 # Apache-2.0
+os-api-ref>=1.4.0 # Apache-2.0
+reno>=2.5.0 # Apache-2.0
diff --git a/setup.cfg b/setup.cfg
index d4a27aec..03bdaad9 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -58,12 +58,6 @@ searchlight.publisher =
 wsgi_scripts =
     searchlight-api-wsgi = searchlight.api.wsgi:init_application
 
-[build_sphinx]
-all_files = 1
-build-dir = doc/build
-source-dir = doc/source
-warning-is-error = 1
-
 [egg_info]
 tag_build =
 tag_date = 0
diff --git a/test-requirements.txt b/test-requirements.txt
index 41160cdb..0aa09c41 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -12,15 +12,9 @@ Babel!=2.4.0,>=2.3.4 # BSD
 coverage!=4.4,>=4.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
 mock>=2.0.0 # BSD
-sphinx!=1.6.6,>=1.6.2 # BSD
 requests>=2.14.2 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 psutil>=3.2.2 # BSD
-reno>=2.5.0 # Apache-2.0
 simplejson>=3.5.1 # MIT
 httplib2>=0.9.1 # MIT
-
-# Documentation
-openstackdocstheme>=1.18.1 # Apache-2.0
-os-api-ref>=1.4.0 # Apache-2.0
diff --git a/tox.ini b/tox.ini
index 7bcfc6ec..582d5f5c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -42,8 +42,13 @@ commands =
   oslopolicy-sample-generator --config-file etc/oslo-policy-generator/searchlight.conf
 
 [testenv:docs]
-basepython = python3
-commands = python setup.py build_sphinx
+deps =
+    -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
+    -r{toxinidir}/requirements.txt
+    -r{toxinidir}/doc/requirements.txt
+whitelist_externals = rm
+commands =
+  sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:api-ref]
 basepython = python3