1 files changed, 1 insertions, 1 deletions
diff --git a/setup.py b/setup.py
index 411f5d9a0..55cd9aa28 100644
--- a/setup.py
+++ b/setup.py
@@ -42,7 +42,7 @@ tests_require = [
 ]
 
 docs_extras = [
-    'Sphinx >= 1.8.1',  # Unicode characters in tree diagrams
+    'Sphinx >= 3.0.0',  # Force RTD to use >= 3.0.0
     'docutils',
     'pylons-sphinx-themes >= 1.0.8',  # Ethical Ads
     'pylons_sphinx_latesturl',