The private security industry is large and diverse, and commonly employed protective measures include intrusion alarm systems, locks, uniformed security officers, barriers, access control systems, fire protection equipment, risk management programs and insurance policies, and investigation of loss-causing events. These protective measures offer various career opportunities for high school and college students. Those considering an investigatory career should realize that many States require private investigators to be licensed, and some jobs require a degree. Private investigators often hire college students on a part-time or occasional basis. All investigators must be skilled in interviewing and report writing. Some jobs require specialized skills; for example, accounting backgrounds are necessary for persons wanting to focus on financial and organized crime. In addition, criminalistics and the field of paralegals involve specialized skills. Consideration is given to jobs in retail, mall, hotel, nuclear, bank, campus, hospital, and airport security. General career advice is offered, along with tips on professional certification and promotion.