Abstract: A proximity switching system comrising a plurality of self-propelled vehicles mounted in tandem on a track and carrying magnetic proximity switches for controlling the vehicle propulsion. Each vehicle has a first magnet mounted on the front end at a first position, a second magnet mounted on the back end at a second position, a first magnetic reed switch mounted on the front end at a position congruent with the second position on the back end, and a second magnetic reed switch mounted on the back end at a position congruent with the first position on the front end. A pair of electric rails are mounted next to the track. Each vehicle includes contacts for receiving voltages on the rails. A DC motor drives the vehicles on the track in one of two directions dependent on the polarity of the voltages, and for not driving the vehicles in response to the closure of the first switch when the voltage has one polarity and in response to the closure of the second switch when the voltage has an opposite polarity.