trained to handle these situations as well as possible. Providing such training is one way developing countries can improve traffic patterns in large cities for a relatively low cost.

Road pricing, a financial method for traffic management, employs a market mechanism to encourage the use of higher-occupancy vehicles and more efficient use of road space. The basic idea of pricing the use of roads for revenue purposes is an old one. In many countries, turnpikes of the late seventeenth and early eighteenth centuries were built as private toll roads. During the modern era, numerous toll roads have been built by public agencies, and tolls have long been used to finance unusually expensive bridges or tunnels. A newer variation on this idea is that of congestion pricing, i.e., charging each motorist a fee that is directly related to the amount of congestion he or she causes in using a road. In other words, roads are priced according to demand, making it more expensive to drive during peak periods than during low-travel periods (Gómez-Ibáñez and Small, 1994).

One advantage of congestion or peak road pricing is that it encourages motorists to find many ways of reducing congestion rather than promoting only a few, such as public transit and carpooling programs. For example, flexible motorists can change the time of day, route, location, or frequency of their travel, as well as switch to other modes. In addition, congestion pricing applies to all motorists who are causing congestion during peak hours and not just to captive groups such as commuters. ¹

Area pricing measures represent a form of road pricing within specific physical boundaries that does not necessarily require sophisticated technology. Area pricing schemes charge drivers if they enter a designated area; normally, the driver must buy a pass in advance or pay a fee at a toll booth located at the entrance to the area. Yet it should be noted that area pricing schemes can result in traffic jams at collection points and should be implemented with alternative forms of downtown transport to protect downtown business activity.

Several urban centers have experimented with area pricing schemes to earn revenues for road construction. Singapore, however, developed an area licensing scheme in 1975 to reduce central city car traffic (Gómez-Ibáñez and Small, 1994). The scheme was initially limited to cars entering the central business district in the morning rush hour. Carpools of four or more people were exempt; other car owners who wanted to enter the center city area during the restricted morning hours were required to purchase a sticker in advance and place it on the windshield of their automobile. The program immediately reduced the number of

Front Matter (R1-R12)

Options for Improving Labor Markets for Megacities in the Developing World (1-34)

Water and Sanitation Services for Megacities in the Developing World (35-64)

Transportation Options for Megacities in the Developing World (65-111)