>Basically, that's all you need to know to get started. The multithreading capabilities in VFP COM servers is to allow them to be more scalable, in that there is no blocking when the server is hit with multiple clients. With a single-threaded COM server, if a client hits it with a, say, a query that takes 30 seconds, any other clients that come in after that have to wait 30 seconds plus however long their task takes. In other words, after the first client hits the server, even if subsequent client requests only require a few milliseconds to run, they would still have to wait over 30 seconds. Multi-threaded COM DLLs eliminate this problem.

Good explanation Mike, many thanks for the tip.