diff --git a/MANIFEST.in b/MANIFEST.in
index 9201b0f..811463d 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,5 +1,8 @@
 include LICENSE
 include *.md
+# RELEASING.md documents how a release is cut. That is for this repository, not for anyone
+# unpacking the source distribution, so keep it out of the sdist.
+exclude RELEASING.md
 include *.rst
 include requirements*.txt
 include pywaffle/py.typed