Abstract: The present invention is a rotary switch with illumination capabilities utilizing a light pipe within the rotary switch to carry light from a light source to the outside of the rotary switch. The light source is preferably an LED or incandescent bulb, and the light pipe may be a fiber optic material or a glass tube. In conjunction with the rotary switch is a corresponding knob that includes a lens disposed adjacent the end of the light pipe for dispersing light communicated through the light pipe to a face on the knob. The rotary switch may include multiple lights corresponding to operating conditions of the rotary switch such as nominal and fail, where the operator can determine the condition by the color of light passing through the lens on the knob.