Not ESB This article s lead statement is that BizTalk Server is an Enterprise Service Bus ESB In fact BizTalk Server has always been positioned as an Enterprise Application Integration EAI server ESB is a layer on top of a Service Oriented Architecture SOA and Microsoft provides these capabilities in BizTalk Server as a collection of components and documents in the ESB Toolkit The ESB Toolkit is not part of the default installation of BizTalk Server and I therefore believe the opening statement of the article is misleading Sir Crispalot