The idea is very simple. It just needs you to know the concepts. On the form processing page whenever u find an error just print or echo this : <script type="text/javascript"> err_popup(); </script> e.g. <? if( empty($_POST['firstName']) ) { echo "<script type=\"text/javascript\">"; echo "err_popup();"; echo "</script>"; } ?> Given that the definistion of the JS err_popup() function has been done in the header part of the markup -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php