We have a lock-down procedure in place where each teacher locks room door and secures outside doors where possible. We have twice yearly drills. Once I was able to 'sweep' a passing visitor into my room before I locked the door, since he happened to be in the right place at the right time. What great publicity to the community, right? We have two security people with radio contact, three administrators who patrol without fail during non-class time, video cameras mounted around campus and soon will have a city policeman with an on-campus office. We have no metal detectors, no fencing, no student vs. intruder identification system. We all keep our fingers crossed during periods of full moon and warm weather. So far, so good.