Indoor stair lights are used to illuminate stair treads and changes in elevation so that strong body shadows are not cast up or down the stairs. They are usually recessed in flanking walls, installed into step risers, or concealed in the handrail. Stair lighting provides a path of light to help the safe navigation of building occupants while shielding the spill light to preserve night vision. Stair lights offer localized pools of light that compensate for ambient lighting to produce a more balanced visual composition. They also act as night lights which provide just the right amount of light independently to prevent trips and falls over stairs during the night. To provide flexibility in responding to room activity and available daylight, automatic controls, utilizing motion sensors and photosensors, are installed to operate stair lights.