Abstract: A trailer hitching aid includes a dual transmitter mounted on the forward end of a trailer or other vehicle to be towed and arranged to transmit pulses of infrared light and pulses of ultrasonic sound. A towing vehicle mounts on its rear end an infrared light detector and a pair of laterally spaced ultrasonic sound detectors. The detectors are incorporated in an electrical circuit which includes a computer the program of which operates to measure the time difference between the detection of a light burst and the detection of sound bursts. The time differences then are utilizes to calculate the distance from each detector to the transmitter, and the distances and angles between the detectors and transmitter are displayed on the computer screen as visual indications to direct the operator of the towing vehicle to maneuver the vehicle to back it up and bring the hitch components on the vehicles into coupling registry.