Place linked select boxes on to your page that dynamicaly load items from database using Ajax. Like Category-Subcategory selections. You can chain as many select boxes as you like. Extra filtering parameter for roor select box so all data can be stored in one db table. Tested on FF and IE for windows and now on FF and Safari for mac. In the same file sc_classes.php there is an other class. Called sc_form_elements. Used partialy from sc_ajax_select_boxes. It is a nice form helper class. Adds select boxes, radio groups and check box groups. It is usual to have options on db and have to populate with them select boxes, or show a list of radio buttons or a list of checkboxes. The routine is to query the database and loop throu the selected rows and add elements to the form. sc_form_elements class comes to save time rewriting that peace of code again and again, but still have control over the form.