I assumed (and you know what happens when someone does this) that in a properly created n-tier app the UI-tier is "shielded" from direct access to the DB-tier through use of middle-tier business objects.

Therefore, UI-tier passes business objects back-and-forth from/to middle-tier and middle-tier actually passes data (recordsets) from/to DB-tier, etc.

Most articles/books about VB and n-tier/DNA approach seems to take this path. However, one thing most, if not all sources I've read forget to mention is how you should design reports under this design.

If I'm using VB and the default Crystal Reports, how should I setup the reports on the UI-tier? AFAIK, CR doesn't work with business objects but directly with the data source.