WizBang in my previous post I mentioned that the variable was a property of an instance of an OPC class object. The external process is an OPC server providing real time values from an Industrial Programmable Logic Controller that is controlling a machine process. Although OPC is a bit finicky, I was actually able to modify the OPCItem Class and create a DataChanged Event. Now I just declare my Class Object WithEvents and I'm getting an event from the data change without having to poll.

Thanks to everyone for the help and suggestions.