I beleive the issue is with the key field. Say one of the two columns is a key column and the other is not. When you create a combo box that displays both columns only the key column is stored in the table. Even if you create a combo box that displays only the non-key column, the key column is stored in the table. At least that's how I've seen it work. I've not played with this for some time but if you were to create the table without keys it may work how you want it to. If you set your default value to a value that exists in the key column you should see the result of the second column in the drop-down (when the control source is the second column).