session-management

It’s a very bad idea to modify WP Core files for the ability to use sessions. The best way I’ve found is to call the session_start() from init action hook. function kana_init_session() { session_start(); } add_action(‘init’, ‘kana_init_session’, 1); You can place it in functions.php file of your theme. Detailed article can be found here: http://www.kanasolution.com/2011/01/session-variable-in-wordpress/