A windshield wiper assembly comprising two windshield wipers each driven by a separate motor is described in which a control provides switching signals for switching on and off the wiper motors so as to achieve relatively smooth running of the wipers. In particular wiping areas one motor is continuously switched on and only the other motor, in dependence on the difference of the angular positions of the two wipers, is controlled such that collision of the wipers is prevented when the wiping areas overlap.