Abstract
This chapter describes the use of ATT (Advanced Transport Telematics) for traffic control. A distinction is made between urban traffic control and highway traffic control. The former is mainly associated with junction or network control. A review is given of some important junction control systems such as MOVA and LHOVRA. The network control systems covered include SCOOT, PRODYN and UTOPIA. Highway control systems include: a) incident detection and congestion monitoring; b) ramp metering; c) the use of variable message signs. The improvement of traffic efficiency by supplying the driver with dynamic route guidance, or by providing priority at traffic controlled intersections for buses is also discussed briefly.