In a traditional application server that uses servlets, when a request is dispatched to a thread the service method of the appropriate servlet is called. When the service method returns the response is sent. This is sub-optimal in the case that an asynchronous event must occur before the response can be sent, because the thread running the servlet must block until the event occurs. The invention provides for asynchronous processing of such requests. In one embodiment, the invention provides an extension to the Servlet API which allows the service method to return (and thus the thread to be freed) before the response is ready to be sent. Then when the asynchronous event later occurs the response may be completed and sent.