Abstract
Introducing a system of road-categories may be a useful expedient for all those, concerned with function, use and design of roads. However a system that dictates in detail the design of roads, based on a classification of traffic, cannot be used in urban areas, due to its lack of flexibility. A global classification of the urban road system is preferred meant to improve procedures of decisionmaking and planning, whereas the possibility is maintained to adapt road-designs to the specific demands of the local situation.