Abstract
This paper is a summary of the proceedings of the international symposium held in Paris in May 1983. Emphasis is being put on adequate methods to log the actual lateral position of cars and changes therein. Further tests should give more information on the matter of bends being sharper than they appear at first sight. Centre lines on unlit rural roads are an adequate remedy against accidents, together with markings on intersections and in horizontal and vertical curves. Studies on accident reports seem not to be sensitive enough to give a proper indication. Lines and reflectors should be positioned in relation to the minimum sighting distance. Wet road surfaces do not necessarily cause poor performance of road markings.