> Do you mean OnAfterScroll on the detail or the master query?

master, of course

> On the master dataset this would probably work, but it seems wrong to
> me to have my grid depending on the master where it actually depends
> on the detail query. In my case, the problem is that the master query
> is on a different form, so my grid cannot easily react on events from
> that.

but you can use same DataModules for each form

> I didn't understand "RTFM or even better GSG from Helen". What does
> that mean?

"RTFM"...please be kind to read provided help files before possibly bothering list
"GSG"...Getting Started Guide...not only for beginners but with a lot of useful tips and tricks, isn't it Helen?