diff --git a/git-flow b/git-flow
index de8d9a1..96c2e52 100755
--- a/git-flow
+++ b/git-flow
@@ -90,6 +90,10 @@
 	fi
 
 	# run the specified action
+	# if the subcommand declares a setup() function, call that first
+	if typeset -f setup >/dev/null; then
+		setup
+	fi
 	cmd_$SUBACTION "$@"
 }