Hi, For example i have code looks like this: <?php ... /** * hook_theme() */ function themedemo_theme() { return array( 'themedemo_example' => array( 'arguments' => array('form' => NULL) ) ); } /** * my admin settings form */ function themedemo_example() { $form = array(); $form['example'] = array( '#title' => t('This is just an example'), '#type' => 'checkbox', '#default_value' => FALSE ); return system_settings_form($form); } /** * The function that has to be registered in hook_theme() */ function theme_themedemo_example($form) { $form['example']['#description'] = t('This description was added by the registered theme function.'); $output = drupal_render($form); return $output; } ?> I think this is legal Drupal form. But in this case my theme function do not work. If i remove return system_settings_form($form); and return $form; only theming function work perfect. Where is problem? Thanks for advance. Havran -- Juraj Chlebec aka Havran http://www.fem.uniag.sk/havran - Havranov mini-blog