I've tried many times in varies Forms to follow the steps on Datapig with setting up 2-cbxes. I created a Form called, Co_Cityfrm with the, 'Co' 'City' & 'ZipCode' (the 'ZipCode' fld is really irrelevant) The 1st cbx is the 'Co' (cbxCo) & for the Row Source I have: SELECT Co_City.Co FROM Co_City GROUP BY Co_City.Co ORDER BY Co_City.Co; This cbx is unbound. In the 2nd cbx which is the 'City" (cbxCty) for the Row Source I have: SELECT Co_City.Co FROM Co_City WHERE (((Co_City.PostOffice)=[forms]![Co_Cityfrm].[Co])) GROUP BY Co_City.Co ORDER BY Co_City.Co; For the Control Source I have: "City" which may or may not be correct? My object with these 2-cbx is, depended upon which 'Co'= is selected, I only want to see those "Cities" associated with the selected 'CO'. Right now I'm able to select a Co, but when I try selecting a City i'm asked for a Paramenter Value???