https://www.dotnetzone.gr:443/cs/blogs/abekiaris/archive/2010/03/15/the-logic-module.aspxXaf architecture and especially the model part is great. What it really teach us is how to parameterized our logic/behavior/code and store that parameter in the model in the form of attributes on already existing nodes or on rule nodes see Xaf ValidationelCommunityServer 2.1 SP3 (Build: 20423.1)