I want to reproduce the functionality provided inside help, where a user can start entering text into a text box and the closest match is highlighted in the list box below and this appears in the text box, or the user can select directly from the list. I can't just use a combo box because I want the selection list visible all the time.

Can you not use the on change event to generate a change in the rowsource of the listbox. ie. when the user types a character into the text box the rowsource for the listbox is changed to where searchcriteria = FIELDNAME = TEXTBOXNAME&*

select * from TABLENAME where SEARCHCRITERIA