The paper first discusses the preparation of a law enforcement agency for a large-scale public health emergency. It advises that plans for such an emergency must be applicable to all types of public health hazards. The value of developing an "all-hazards" plan is that it can be activated regardless of whether the public health emergency is intentional or a natural occurrence. By incorporating an "all-hazards approach into routine policing activities and developing the needed partnerships with key stakeholders now, a department can move seamlessly into higher states of readiness as risks change. The discussion of a law enforcement agency's plans for a public health emergency addresses the response to and management of incidents, as well as protecting personnel so as to ensure operational continuity. The second major section of the paper focuses on the protection of officers in the course of a public health emergency. It advises that officers should have basic education about infectious disease biology, modes of transmission, and routes of entry of communicable diseases. Such training might involve a partnership with a local hospital or an occupational health and safety program. Agencies could also provide a short course in preventing on-the-job exposure to infectious diseases through basic precautionary measures and the proper use of personal protective equipment. The paper's third section addresses the protection of the community. The topics discussed are working with public and private agencies, law enforcement's role in mass vaccination and prevention measures, its role during voluntary and involuntary restrictions, its role in mass-casualty planning, and working with special populations. Appended information on quarantine, vaccinations, pandemics, and definitions of key terms