>I've just changed it to IQueryable in the base classes. Now I'll have to fix all application errors due to this change.

OK, I know I've asked this before. Why go through all the trouble on this, when you could just use stored procs or even straight sql pass through? This is low-hanging fruit functionality, IMO being made overly complicated. Not trying to be a pain - would truly like to understand why a development team would take this approach.