diff --git a/hooks/require-plan-file.sh b/hooks/require-plan-file.sh
index 34e8876..2bcbdf0 100755
--- a/hooks/require-plan-file.sh
+++ b/hooks/require-plan-file.sh
@@ -10,6 +10,12 @@ if [ -z "$CWD" ]; then
     exit 0  # Can't determine cwd, allow through
 fi
 
+# Projects can opt out by placing .claude/skip-plan-file-check in their root.
+# Used when the project manages plans via an external system (e.g. a work-items CP).
+if [ -f "$CWD/.claude/skip-plan-file-check" ]; then
+    exit 0
+fi
+
 if ls "$CWD"/*-PLAN.md 2>/dev/null | grep -q .; then
     exit 0  # Plan file exists, allow exit
 fi