Abstract: A method and apparatus are described for detecting obstacles in the “blind spot” of a motor vehicle's side mounted mirrors. Advantageously, the inventive apparatus is mounted on the vehicle as an attachment to the side mirror system or adjacent to it. The invention determines the presence of an obstacle in a sensing volume that encompasses the “blind spot”. The invention relies on the time-of-flight measurement of preferably short infrared pulses to locate obstacles. Multiple sensors are used to provide area coverage. If any sensor detects an obstacle within its predefined range limits then an indication is provided by a display unit at the side mirror location. The system can be used on both sides of the vehicle and each side operates independently.