This plugin extends the default taxonomy functionality and extends it to users, while automating all the boilerplate code. Once activated, you can register user taxonomies using the following code: register_taxonomy('profession', 'user', array( 'public' =>true, 'labels' =>array( 'name' =>'Professions', 'singular_name' =>'Profession', 'menu_name' =>'Professions', 'search_items' =>'Search Professions', 'popular_items' =>'Popular Professions', 'all_items' =>'All Professions', 'edit_item' =>'Edit Profession', 'update_item' =>'Update Profession', 'add_new_item' =>'Add New Profession', 'new_item_name' =>'New Profession Name', 'separate_items_with_commas'=>'Separate professions with commas', 'add_or_remove_items' =>'Add or remove professions', 'choose_from_most_used' =>'Choose from the most popular professions', ), 'rewrite' =>array( 'with_front' =>true, 'slug' =>'author/profession', ), 'capabilities' => array( 'manage_terms' =>'edit_users', 'edit_terms' =>'edit_users', 'delete_terms' =>'edit_users', 'assign_terms' =>'read', ), )); Read more about registering taxonomies in the codex This is heavily inspired by previous work by Justin Tadlock