Combo boxwith a difference

Hi all,

Grateful for assistance/advice.

I have a form with a combo box which selects from a list of data from a particular field in a table. The selected item is then saved in another table...so far so good.

However i would like the combo to show up only a selection of items from that list. In other words i dont want the combo box to show all the list of items for that particular field but only a section of them based perhaps additional data from another field. hence...


field1 - field2
bob - a
jill - a
tom - b
jack - a

I would like the combo box to show only the names of field 1
that has "a" as field 2

Thanks