Generally, nighttime firearms training must be conducted either after dark or be simulated during daylight by wearing sunglasses. Both methods are unsatisfactory for training in low-light shooting. The use of a Dark House permits nighttime training any time, day or night, and in a safe environment, shooters become accustomed to muzzle flashes, and instructors can offer a full range of hands-on training, combining the combat elements of marksmanship, time, and space in a darkened environment. Hillsborough County's Dark House is a 10-stall, 75-foot certified shooting range. Walls, ceiling, and floor are painted a flat black. There are no windows, and the doors open behind a protective wall in order to reduce light from outside the building. Inside lighting is provided by red bulbs that allow shooters and trainers to see their targets, be visually safe, and understand what is happening around them as they shoot and reload. Overhead, black lights simulate a full moon. Regular white lights provide illumination when the range is not being used. The aim of the Dark House is to provide officers with a shooting environment that approaches the conditions of real low-light or night conditions. Training in the Dark House enables officers to become familiar with the muzzle flashes visible only in the dark and the use of flashlights to illuminate targets when firing and to aid in reloading. In addition to describing the Dark House and its training purposes, this article also explains the eye adjustments that occur when moving from a lighted area to a low-light or dark area. Photo illustrations