Abstract: The present invention relates to an adjusting apparatus having an optical aimer (2) that includes a reflector (2.1) for adjusting parts of a motor vehicle, in particular distance warning radar, headlights, or an axle; having an emitting device (3) that emits a collimated beam (3.4); and having a vertical adjusting device (1) for orienting the reflector (2.1) at a certain angle (&bgr;) to a floor (5) of a measuring station forming the contact plane of the vehicle. An exact vertical alignment or orientation at a certain tilt angle to the floor of the measuring station is achieved by simple measures, in that the emitting device (3) is positioned in a vehicle region remote from the aimer (2), at a specific, defined level (h) of the vehicle above the measuring-station floor (5) and may be adjusted for emitting the beam (3.