The invention relates to a method for detecting the passage by a vehicle of a determined point for monitoring on a road, wherein from a remotely situated location a laser beam is transmitted continuously to the point for monitoring, reflections from the transmitted laser beam are received at the remotely situated location, and it is determined from the received reflections that the vehicle is passing the point for monitoring. The laser beam can be transmitted at right angles to the travel direction of the passing vehicle. The detection can be used to activate a red-light camera, to measure the speed of the vehicle or measure the traffic intensity, without sensors, for instance induction loops, having to be arranged in the road for this purpose. The invention further relates to a system for performing this method.