Recently, investigations of vehicle navigation systems and traffic control systems have been accelerated by new developments in electronics and by social requirements. In Japan especially, the appearance of new media and the interest of public organizations have an influence on this. Navigation systems are classified into two types. One is the stand-alone type and the other is part of the large social system.In this paper, the stand-alone navigation systems for passenger cars are discrived. For passenger car use, the system should be easy to operated and with minimum cost and size. In this respect the concepts of guide and the elements of navigation (such as data on the network structure of the road optimum route calculation method, position sensing and definition, guide algorithm, command input procedure, etc.) are examined. Based on these studies, a proto type system is designed at the actual product level and tested. The proto type system is composed of a 6-inch CRT, magnetic compass sensor, speed sensor, 1M bit ROM memory, optical links and many CPUs. For the test, the system could guide the driver to the target point 200 km away from the starting point, while some problems are pointed out.