diff --git a/.travis.yml b/.travis.yml
index 78b4410c7454e21a9daf2e5a7d087c0277a95018..92d0a377e6f21ee135c9385ffdee2551b2a0cf57 100755
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,6 +9,7 @@ install:
   - pip install --upgrade pip
   - pip install --progress-bar off -e .[develop]
   - pip install sphinx
+  - pip install sphinx_rtd_theme
 
 script:
   - cd docs