This sample shows how to use a simple Concurrent (Parallel) Convoys inside an Orchestration. For more information on Convoy, be sure to read the Convoy Deep Dive White Paper.
This sample also shows an example of multi-message mapping inside an Orchestration.
This sample should work for BizTalk 2004 and BizTalk 2006.
Get more information from the original blog post on this topic: http://www.biztalkgurus.com/blogs/biztalk/archive/2004/11/08/Parallel-Convoys-_2800_Concurrent-Receive_2900_-in-BizTalk.aspx