Hi All, I am trying to run Exchange 2k in an ASP environment and have hit a problem with regards to Address Lists. So far I have been able to lock down the lists by given each of our customers a unique custom attribute number, then filtering on the global address list so that the customer can only see addresses relevant to their company. I have come unstuck when trying to setup distribution lists (universal AD groups) as the GAL filter logic is AND, not OR. Therefore I cannot show Users AND Groups in the same list. How can I setup a distribution list for our customers? I can't use the address list container (as opposed to the global address list container) as it can't be secured well enough so that one cutomer can't see another customer's addresses. Thanks for your help Oli.