I have an application that I wrote with VB6 several years ago, and I have continued to modify/improve on the code so that it can execute faster. I took some heavy math and placed it in a DLL. I'm looking around my code to see what else I can move. I don't know if there would be any point to moving something like a simple incrementation of a number, i.e. A = B + 1. I have some string operations that I might be able to move. It's a function returning a value, so I don't see a reason not to. I don't see any point of putting a Sub in a DLL since it can't return anything to the external caller. The only reason I see to put a Sub in a DLL is if a function residing in the DLL could use it internally. There was a very noticeable performance improvement by creating the DLL. Note: It is not a VB6 DLL. I created it with another platform. If anyone has any comments, I would like to hear them.