A reflector/refractor device is provided for use with a variety of lighting fixtures and light sources. The reflector/refractor device includes a body having a predetermined profile and defining a cavity with the body having an inside surface and an outside surface. An illuminating source for emitting light is disposed within the cavity substantially along a central vertical axis of the body. The body includes a series of sectional zones for reflecting and refracting light. The exterior surface of the device includes a plurality of substantially vertical prisms consisting of reflective elements, refractive elements and elements that may be either reflective or refractive depending on light center location. These reflective or refractive elements act in combination to selectively vary light distribution characteristics of vertical and lateral angles, and intensities, by vertical displacement of the illuminating lamp source.