Should I maintain relationships diagrams in the back-end and the front-end? I’m developing an Access 2010 database application. It is split into a back-end, holding all the tables, and a front-end, holding all the queries, forms, etc.
I find the Relationships tool helps provide an extremely valuable visual resource (an ERD), in the back-end, and know that Access uses it to enforce integrity.

So far, however, I’ve never used the same tool in the front-end. I have many more queries than tables but have never seen them in form of an entity-relationship diagram. Have you ever found it useful to diagram your queries using the Relationships tool? Any advice on what practice has worked well for you?
I have never used the relationships tool for anything other than understanding the relationships between base tables on the back end database.  I could see however where it would be very useful on the front end if you have many users of your application who write a lot of ad-hoc queries and you provide them queries stored on the front end database which they can use as an abstraction layer.  On the other hand, if the users only interact with the database via forms I would think the work to add the queries to the relationship tool and connect them up would not be worth it.