>>>You can also reduce the number of "hits" by checking, not when an expression changes, but when it becomes true.
>>
>>Gracias, Hilmar,
>
>De nada.
>
>>I presume there is no way to place a UDF in the watch window and have it recalculated when the watch window refreshes, right?
>
>I don't have VFP with me right now. I thought all expressions - including UDFs - placed in the watch window would be re-evaluated, but I may be wrong.

Nope, only VFP internal functions get evaluated in a watch window. UDFs do not. UDFs show up as (Expression could not be evaluated).