it's called a cascading combo box, create a secondary combo box where the contents of the field you want to say (say first name) and put in the last name with a criteria of [forms]![formname]![lastnamefield] where formname is the name of your form and lastnamefield is the name of the field that contains your last name. Then in the ON EXIT property of your lastname field put in [firstnamefield].requery, this will force the firstname field to requery your database looking for all the firstnames of anyone with the surname of smith
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