Abstract
This chapter describes a new way to improve traffic conditions by introducing interactive dynamic route guidance (DRG) and driver information (DI) systems. It has a successful three year field trial in Berlin. The principle of system operation is described first. The methods by which drivers are routed to available car parks or alternative modes of travel are presented. Other types of information which could be incorporated into the system are also discussed briefly. These include weather hazard reports and tourist information. Methods for collecting and storing the data necessary for providing the information are presented. The POLIS initiative is also described briefly.