Abstract: A shoe in the side of its upper or along its outsole has a transparent diffusing element with a convex front face and a multitude of facets in its back face. A pocket opens out of the back face and contains a light emitting diode which is connected to a energizing module in the outsole of the shoe. The circuit contains a switch which is sensitive to impacts, and a battery, and when the switch is subjected to an impact of sufficient magnitude, the circuit impresses across the diode an electrical potential that is derived from the battery. The electrical potential illuminates the diode and the illumination spreads through the diffusing element, reflecting off the facets of its back face so that the diffusing element illuminates large areas on the shoe.