A protective lighting system should illuminate the approaches to the facility and the perimeter barrier, along with the area between the perimeter barrier and all structures located within the protected area. Lighting should be directed downward and away from all structures and from security personnel assigned to patrol the facility. The goal is to create as few shadows as possible. Perimeter lights should be installed so the cones of illumination overlap, eliminating areas of total darkness if any one light fails. The lighting system can be protected by installing all fixtures inside the perimeter barrier at a high level and enclosing them in vandal-resistant housing. Power lines should be buried and switch boxes protected. A gasoline or diesel generator should be used as a backup system in the event of power failure. This article provides information on the minimum intensity recommendations for outdoor protective lighting and describes the five basic types of lighting as well as types of light sources. 3 exhibits.