This handbook is an update of the 1983 edition and reflects the tremendous developments in computing and communications technology. It also reflects the importance of "Integrated" Transportation Management Systems and the development of the concept of Intelligent Transportation Systems (ITS). The handbook development began with a survey of current practice, including site visits and interviews, of ten Freeway Management Systems throughout the country. It was developed under the advice of a panel of freeway management practitioners. The 1997 edition is organized in modular fashion with each module addressing a particular aspect or technology of the freeway management task. The modules are stand-alone treatments of particular areas of freeway management but are cross-referenced to reflect their interdependence