I am trying to change the checkboxes for the terms on the backend to radiobuttons. I found this topic: https://wordpress.stackexchange.com/questions/7456/altering-the-appearance-of-custom-taxonomy-inputs however wich helped me doing this. However, this will turn ALL terms checkboxes to radio buttons. Is it possible to apply this only for one taxonomy? My code: add_action('add_meta_boxes','mysite_add_meta_boxes',10,2); function mysite_add_meta_boxes($post_type, $post) { ob_start(); } add_action('dbx_post_sidebar','mysite_dbx_post_sidebar'); function mysite_dbx_post_sidebar() { $html = ob_get_clean(); $html = str_replace('"checkbox"','"radio"',$html); echo $html; } thanks