The BW IRP, led by the U.S. Army's Soldier and Biological Chemical Command, is a multiyear, multiagency effort that was begun in April 1998. The initial program team was composed of over 60 Federal and State experts, local responders, and technical experts. The BW IRP consists of 13 components under the following 3 phases of response: continuous surveillance, active investigation, and emergency response. Continuous surveillance involves the constant monitoring of public health patterns throughout the country in an effort to detect any unusual health event in any jurisdiction. Based upon evidence that an unusual health event has occurred, an active investigation is then conducted. This involves expanded surveillance that consists of medical diagnosis, epidemiological investigation, and criminal investigation. Key decisions to be made in the course of the investigation are whether a major public health event has occurred and, if so, the cause and population at risk; prophylaxis, treatment, and isolation; and appropriate emergency response. The emergency response involves the establishment of a command and control center that will coordinate the following activities: hazard assessment mitigation and control, prophylaxis and immunization, public information, care of casualties, control of affected area and population, resource and logistical support, continuity of infrastructure, fatality management, and family support services. In developing a BW IRP program for a community, the following planning issues must be addressed: who will be in charge of the community response, what scale of biological attack is to be addressed in planning, the role of emergency management, and the strategy for dealing with potentially exposed patients and critically ill victims when local hospital capacity is exceeded. 3 figures, 24 references, and appended military installation response, regional response, and points of contact for planning assistance