Abstract
The concept of sustainable safe traffic was launched in The Netherlands in the beginning of the nineties. Since then, perhaps the most well known work concerns the categorising of roads in order to clearly define design principles etc for each category. The paper stresses the importance of recognition and predictability. If the road network is to be categorised the road user must be familiar with the road type. Furthermore he must know what behaviour is expected from him and he must know, within certain limits, what behaviour he could expect from other road users.