Since my last post I have now created the basic listings of the forum, including categories, threads in a category and answers to a thread. I did allso decide to use Linq to NHibernate to cunstruct my queries instead of the criteria API. I made choise because I think a linq query looks nices then a criteria query, and you will reduce a few more "magic strings". So far, my repository interfaces looks the same as before, so I still return a IList from my repository. I might change this to IQueryable in the future, I haven´t decided this yet. So if you have a good reason to do eather one of them, do please tell me.