But if I dele a record in the table and then say
thisForm.Grid1.SetFocus()
nothing appears in the grid, even though a browse of the table
shows that it still has records. Why is that?

Are you PACKing the table after you delete the record? PACKing the table closese it behind the scenes and rips the grid's RecordSource out from under it, causing it to go blank. You do not need to pack the table after deleting the record. All you need to do is (with DELETED SET ON) move the record pointer in the table to get the deleted record to disappear from the grid.