New York City is set to become the first American metropolis that seeks to ease traffic congestion, cut pollution and boost mass transit by charging motorists a hefty toll for the privilege of driving into its most crammed areas. So can it work? If the experience of other cities around the world that have tried it is any indication, the answer appears to be yes. London, Singapore and Stockholm have all reported that "congestion pricing" systems similar to the one now being planned for Manhattan led to initial reductions in traffic and improvements in air quality, while creating a steady stream of revenue to support public transit and other infrastructure.