BizTalk - Scatter / Gather Pattern

We recently encountered a BizTalk Orchestration Design problem: How do we maintain message flow when a message needs to be sent to multiple recipients, each of which may or may not send a reply, and then aggregate the response from all recipients into one message?

The Solution: One of BizTalk’s many powerful features is its ability to loosely couple messages, which allows for the subscription-based processing of messages. The ability to route messages based upon content filters makes BizTalk a great fit for the Scatter/ Gather pattern.

The Scatter/ Gather pattern is a method for broadcasting and processing messages in parallel. The "scatter" portion distributes a series of messages, all at the same time, and then an aggregator "gathers" the messages back into the main response before continuing.