diff --git a/marketplace.js b/marketplace.js
index 7e4b734..d8765ba 100644
--- a/marketplace.js
+++ b/marketplace.js
@@ -118,6 +118,10 @@ function sendMessage(m, metaLevel, isFeedback) {
 	     isFeedback: (isFeedback === undefined) ? false : isFeedback };
 }
 
+function shutdownWorld() {
+    return { type: "shutdownWorld" };
+}
+
 /*---------------------------------------------------------------------------*/
 /* Metafunctions */
 
@@ -218,6 +222,10 @@ World.exit = function (exn) {
     World.current().killActive(exn);
 };
 
+World.shutdownWorld = function () {
+    World.current().enqueueAction(shutdownWorld());
+};
+
 World.withWorldStack = function (stack, f) {
     var oldStack = World.stack;
     World.stack = stack;
@@ -373,6 +381,9 @@ World.prototype.performAction = function (pid, action) {
 	    World.send(action.message, action.metaLevel - 1, action.isFeedback);
 	}
 	break;
+    case "shutdownWorld":
+	World.exit();
+	break;
     default:
 	throw { message: "Action type " + action.type + " not understood",
 		action: action };