>In real life, how big can we handle with a vfp6 application on native databases (on a NT 4) ? For a standard business application (accounting, invoicing, ordering, inventory, etc...), is there anybody running around 50 users ? What is the performance ? At this size, is it absolutely needed to go client-server ?

I have over 100 users with multi-user DB, all native vfp. I'm not sure what the max simultaneous users has been, probably 30 or 40. No problems with performance, the system is large but quite fast, and we have some tables up to 500 MB.

On the other hand, we have a PB/Sybase C/S system, about the same size app, that slows to a crawl with 10 users and 1 MB of data. They are really struggling to get it faster. So C/S won't necessarily solve all the problems by itself...it has a lot to do with application and DB design.