Nadya,

Have you considered using a combination of a TextBox with an input mask for input, a set of add/remove buttons and a listbox?

The user would type in the zipcode in the TextBox where it could be easily validated, then click the Add button to add it to the ListBox. Remove would be used to remove items from the listbox.

>Ken,
>
>>Is the EditBox bound to a memo field?
>
> No. I just want to use user's input for selection criterion. That's it. No bound to.