diff --git a/crates/matrix-sdk-crypto/README.md b/crates/matrix-sdk-crypto/README.md
index 25cbb7b7d..c8806eb25 100644
--- a/crates/matrix-sdk-crypto/README.md
+++ b/crates/matrix-sdk-crypto/README.md
@@ -44,3 +44,10 @@ async fn main() -> Result<(), OlmError> {
 
 [Matrix]: https://matrix.org/
 [matrix-sdk]: https://github.com/matrix-org/matrix-rust-sdk/
+
+# Room key sharing algorithm
+
+The decision tree below visualizes the way this crate decides whether a room
+key will be shared with a requester upon a key request.
+
+![](https://raw.githubusercontent.com/matrix-org/matrix-rust-sdk/main/contrib/key-sharing-algorithm/model.png)