OK, this is where I'm at now. I got the sorting working by adding back in ORDER BY lastname ASC. So now, only one thing wrong with the list_users.php file: whenever I click on EDIT or DELETE, it links to the correct file (either update_user.php or delete_user.php) but it's not prepopulating the form with the user's data. I have this set up identically to update_self.php, but in this case I'm getting a blank form. Thank you once again for your help.