My experience with EJB framework is quite limited, but the following is the way I am working in my current project.
I think the difference between Business Delegates and Session Facade is about how you package your application.
If you design to divide your J2EE application into Web side and App side, then the Web side is placed in the Web server while the App side is placed in the App server. They can either be located in the same machine, or physically in 2 separate servers. Business Delegates should be placed in the Web side, along with those Action classes / servlets. On the other hand, Session Facade objects are located on the Application side. My view is that it is the Business Delegates that make calls to the corresponding Session Facades through their remote interface. [ May 31, 2004: Message edited by: Wendal Park ]