The cancel or stop button would change the value. Again, VFP probably won't allow keypresses until the current process is finished.

I've had another thought on this: if you could split the processing up into chunks (ie prevalidate, validate, postvalidate, preprocess, process, postprocess) then VFP should be able to check between each of the processes.

>If the process checked for a value change - how would the value become changed from the user in the first place?
>
>Kev