diff --git a/.github/workflows/warden.yml b/.github/workflows/warden.yml
index 8eb2b2c..26c71bb 100644
--- a/.github/workflows/warden.yml
+++ b/.github/workflows/warden.yml
@@ -1,9 +1,14 @@
 name: Warden
 
+# Update the concurrency group below if this workflow adds non-PR triggers.
 on:
   pull_request:
     types: [opened, synchronize, reopened]
 
+concurrency:
+  group: ${{ github.workflow }}-pr-${{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
 jobs:
   warden:
     if: github.event.pull_request.head.repo.full_name == github.repository
diff --git a/warden.toml b/warden.toml
index 3b66325..e78d9cc 100644
--- a/warden.toml
+++ b/warden.toml
@@ -1,3 +1,5 @@
+# Organization-wide Warden configuration.
+# Shared workflows load this file as their base configuration.
 version = 1
 
 [defaults]