problem with using link variables

Hello, I am sending variables via a link to another page eg. <a href=\"agencydet.php?provnum=$provservid\">$provservdesc</a> If the variable provnum contains text such as: hello & there Then only the word hello is passed on to agencydet.php. I have tried using htmlspecialchars and htmlentities but still I have the same problem. What I am trying to achieve is to be able to display hello & there on the agencydet.php page when it is shown in the browser. Thanks, Ivan