diff --git a/README.md b/README.md
index e1858a9..cacc284 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,7 @@ NIPs stand for **Nostr Implementation Possibilities**. They exist to document wh
 - [NIP-16: Event Treatment](16.md)
 - [NIP-22: Event created_at Limits](22.md)
 - [NIP-25: Reactions](25.md)
+- [NIP-27: Multicasting](27.md)
 
 ## Event Kinds