Architecture and Design

http://social.technet.microsoft.com/wiki/contents/articles/5280.using-visio-2010-bpmn-to-design-model-and-document-biztalk-solutions.aspx

http://social.technet.microsoft.com/wiki/contents/articles/5193.biztalk-server-documentation.aspx#Tooling

http://msdn.microsoft.com/en-us/library/gg634499%28BTS.70%29.aspx