diff --git a/docs/requirements.txt b/docs/requirements.txt
index 43dbc0817..03ecc7e26 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,2 +1,3 @@
 emdfile
-# py4dstem
\ No newline at end of file
+sphinx_rtd_theme
+# py4dstem