DEAR MISS MANNERS: I have a question about protocol, as my husband's family is rather well connected and I know a large number of people of relatively high stature in my community. If I am talking with a friend at a cocktail reception and am approached, mid-sentence, by, say, the mayor, do I turn abruptly away from my friend to greet him? Conversely, if I am speaking with the mayor and my friend interrupts, how do I react?
GENTLE READER: "Oops, there's the mayor, wait, I have to ask him when they're going to pick up the trash in my alley."
Mayors love this opening, Miss Manners assures you, and friends don't mind being interrupted by it because it gives them the chance to tell the mayor about the trash in their allies.
Otherwise, when anyone approaches while one is chatting at a party to someone else, the rule is to smile at the newcomer, finish what one was saying and then introduce everyone and include him in the conversation.