Ranzi
Queries are not designed for (and don't have) a drop-down capability.
If you want to provide your users a list of valid values, use a form. Then,
in your query, 'point' to the form's combobox, using something like:
Forms!YourForm!cboYourCombobox
as the selection criterion for that field.
You'll need to add a command button to the form to have the users <Run
Query>, and the form will have to be open (and a combobox item selected) for
the query to work.
Regards
Jeff Boyce
Microsoft Office/Access MVP