The 51st World Science Fiction Convention (Worldcon), also known as ConFrancisco, was held September 2–6, 1993, at the ANA Hotel, Parc Fifty Five, and Nikko Hotels, and the Moscone Convention Center in San Francisco, California, USA.The supporting organization was San Francisco Science Fiction Conventions, Inc. The chairman was David W. Clark. The Guests of Honor (called "Honored Guests") were Larry Niven, Alicia Austin, Tom Digby, Jan Howard Finder, and Mark Twain (Dead GoH).