function delete() {
		// delete system permissions
		SystemPermissions::delete("`permission_group_id` = ".$this->getId());
		// delete member permissions
		ContactMemberPermissions::delete("`permission_group_id` = ".$this->getId());
		// delte dimension permissions
		ContactDimensionPermissions::delete("`permission_group_id` = ".$this->getId());
		// delete contact_permission_group entries
		ContactPermissionGroups::delete("`permission_group_id` = ".$this->getId());
		// delete tab panel permissions
		TabPanelPermissions::delete("`permission_group_id` = ".$this->getId());
		
		parent::delete();
	}