diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 376e4617c3d50531e4996ee7dc0fcbe82a4a177c..451016d8f0221678249fc7b6d745d6e3569c2891 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -30,6 +30,6 @@ sphinx:
 # Optional but recommended, declare the Python requirements required
 # to build your documentation
 # See https://docs.readthedocs.io/en/stable/guides/reproducible-builds.html
-# python:
-#    install:
-#    - requirements: docs/requirements.txt
+ python:
+    install:
+    - requirements: source/requirements.txt
diff --git a/source/requirements.txt b/source/requirements.txt
new file mode 100644
index 0000000000000000000000000000000000000000..ddff895cd516e517e379dc6d1dcbb9d11391a57b
--- /dev/null
+++ b/source/requirements.txt
@@ -0,0 +1,3 @@
+# Defining the exact version will make sure things don't break
+sphinx==3.4.3
+sphinx_rtd_theme==0.5.1