When typing say Claire in the To box in Worldclient, it defaults to show all the Claire's in the address books and doesn't seem to use a history or suggested contacts list.

My clients are schools and they have access to the Council Address book which has about 800 Email addresses in it. Most of these addresses are never emailed to, but they show first when typing a name because of alphabetical order.

My recommendation would be to change this to use suggested list or frequently used contacts first, followed by local address books and then public address books otherwise for big Public Address Books you are seeing a long list of people named Claire or Mark first that you never email and you always have to scroll down to the Mark or Claire that you actually want to email.