diff --git a/MANIFEST.in b/MANIFEST.in
index aa16b485..57e06c65 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -4,7 +4,7 @@ include LICENSE *.rst
 exclude *.md .travis.yml
 
 # Tests
-include tox.ini .coveragerc conftest.py dev-requirements.txt
+include tox.ini .coveragerc conftest.py dev-requirements.txt docs-requirements.txt
 recursive-include tests *.py
 
 # Documentation
diff --git a/docs-requirements.txt b/docs-requirements.txt
new file mode 100644
index 00000000..5125a07f
--- /dev/null
+++ b/docs-requirements.txt
@@ -0,0 +1,3 @@
+-e .
+sphinx<1.6
+zope.interface
diff --git a/tox.ini b/tox.ini
index 5229b473..61eea75f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -27,9 +27,7 @@ commands = flake8 src tests setup.py conftest.py docs/conf.py
 basepython = python3.6
 setenv =
     PYTHONHASHSEED = 0
-deps =
-    sphinx<1.6
-    zope.interface
+deps = -rdocs-requirements.txt
 commands =
     sphinx-build -W -b html -d {envtmpdir}/doctrees docs docs/_build/html
     sphinx-build -W -b doctest -d {envtmpdir}/doctrees docs docs/_build/html