Some key objectives of the ITS community are to improve the efficiency of the nation's highways using proven technologies; allow for future expansion and growth; and allow for incorporation of emerging technologies. This paper describes the design of an Advanced Traffic Management System (ATMS) for Interstate 476 (I-476) that fulfills these objectives. The ATMS on I-476 blends conventional sensor technologies with several communications technologies. Client-server architecture provides shared access to the system database and controls for control center personnel and other outside agencies. The system combines real-time data for graphic displays with an open architecture for network and communications services.