Claude Fischer is a French-born American sociologist. He received his Ph.D. from Harvard University and currently teaches sociology at the University of California, at Berkeley. Most of Fischer's work focuses on urban society. He has written extensively on structural changes in modern society and has researched social networks and the displacement of traditional territorially based communities by new communities of human association. Fischer is also interested in the impact of technology on social relations and social institutions; most recently, he has investigated the social history of the telephone.