In ajax, there are several cases where you need to call a bunch of actions synchronously. That means one action must finish before another one called. You can do it by checking the status of ajax request of previous calls and if that was in finished state, you can call next action. This process may be resource extensive if you dont care for checking. So here is a simple actionChain object which will help to put numbers of actions in a chain (or you better say, queue) and call them one of after one smartly.