Abstract
From November 1, 1979 a red reflector on the rear side of bicycles became compulsory in the Netherlands. At present almost all bicycles are provided with a reflector, but of the racing-bicycles only 12-15% complies with the new rule. Counts were carried out by SWOV at five sites in various parts of the country between 4 and 7 p.m.: in a town center, in a village, on two separated cycle tracks along busy main roads with commuter traffic in a cycle-store of a secondary school in a suburb of The Hague.