A high rise is exposed to all the normal security risks of a street-level structure, but the uniqueness of its physical stature calls for a different protection approach. Tall buildings house a high population in a concentrated area. Movement is restricted to elevators and stairwells. Limited entrances and exits cause another safety concern. The swell of humanity and numerous corridors provide anonymity for plotting criminals and terrorists. From underground garages to the roof, a successful high rise security plan tackles challenges literally from the ground up.