By floodlighting the outside of your store on all sides you can defeat many burglars. All sides include alley entrances and side passageways between buildings where entry might be made. Mercury and metallic vapor lamps are good for illuminating the exterior walls of a store. They are designed to withstand vandalism and weather-wind velocities up to 100 miles per hour. Some have a heat tempered lens that cannot be broken with less than a 22 caliber rifle.
Indoor lighting is also important.
When a store is lighted inside, police officers can see persons in the store or notice the disorder which burglars usually cause. When the store is left dark, a burglar can see the police approaching, but they can't see the burglar. Police get to know the lighted stores and will check the premises when, and if, the light is off. It is also important to arrange window displays so police patrols can see into the store. Be sure the safe in which you keep your money and other valuables is strong enough to deter burglars.