Warehouses have various openings intended to facilitate the orderly flow of cargo in and out of the facility. These openings should be controlled by alarms directed to a central point in the compound for instant response by the guard force. Inexpensive magnetic switch contacts should be placed on all perimeter doors, high-value fenced enclosures, and key office areas. In warehouses that do not operate continuously, some type of internal space protection should be installed. Sensor options included ultrasonic detectors, microwave motion detectors, photoelectric systems, and closed-circuit television. Other considerations for physical security include fencing, lighting, separation of employee facilities from the warehouse, and controlled employee entrances and exits. Guard force effectiveness depends on careful selection of personnel, proper dress, intensive training, written instructions, and appropriate followup. Close guard supervision is required, including regular inspection on a surprise basis. All posts and patrols should be checked and evaluated. Loss-prevention programs might focus on employee photo identification, visitor control, gate passes, master gate records, package passes, facsimile signatures, gasoline and diesel fuel control, trailer and truck seals, emergency procedures (bomb threats), and receiving and shipping operations. Distribution security should address trailer security at the warehouse, at inhouse units (stores), and in transit. Guards should conduct a trailer security check at the main gate, and control should be exercised over vendor vehicles. Procedures must also be developed for hijack investigations.