> I can know how many rows was selected, but need to access some field
> for I := 0 to IB_Query1.RowsSelected-1 do
> if IB_Query1.selected[I] then
> // HOW can I access some field at THIS point?

Now you are on a selected row and you can do with your field whatever you want by addressing the
single fields for example by fieldname:
IB_Query1.FieldByName('MyFirstField').AsInteger := 12345;
IB_Query1.FieldByName('MySecondField').AsString := 'FooBar';
.....


Florian