Thanks - that has set my mind at rest. I've also been forgetting to award stars - you've all been very helpful.

>A quote from the article "Control of Call Blocking" ( http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fox7help/html/newcontrolling_call_blocking.asp )
>
>The Visual FoxPro implementation of Apartment-model threading eliminates conflicts in accessing global data from multiple threads by giving each apartment its own copy of global data. This means that all objects created on the thread exist in this apartment, and are unaware of objects in other apartments.