Three written-to-order novellas about futures where instantaneous movement through space and time is as prosaic as traffic jams today. Niven deals with what happens to law enforcement -- specifically riot control -- when everyone travels by displacement booth. Brunner's mordant tale postulates colossal screw-ups by the minions of Transmatter, Inc. And Vance spins an odd tale of a society where anyone can homestead his own alternate probability world, leading to novel forms of old-fashioned aberrations. Some intriguing notions, but a little thin.