When dealing with time-consuming requests, the use of an asynchronous message exchange pattern (MEP) can be a good option. One style of asynchronous exchange, sometimes called "decoupled endpoint," involves an initial one-way request (no response) from the client to start a long-running process, and then, on completion, the service makes a one-way "callback" to the client that contains the result. The WS-Addressing policy's ReplyTo and MessageID properties are often used to allow the client to specify the callback address and identify related messages over the asynchronous exchange.

To demonstrate how SoapUI can test and mock such an interaction, this recipe covers the example of a quote service that provides a callback that contains dummy quote details after a quote request is made for some dummy products.