structures, and the broader environment, and they may be caused by a wide range of natural, technological, and deliberately introduced agents. This variety of factors explains the complex array of disciplines and organizations involved in the emergency and disaster response field. The category of first responders has typically included personnel from the fire-fighting, EMS, and law enforcement fields, along with state emergency management agencies and federal agencies (e.g., Federal Emergency Management Agency, Environmental Protection Agency), and nongovernmental organizations, such as the Red Cross and the Salvation Army. Other disciplines involved in preparedness include structural engineers, civic planners, public administrators, etc. Clearly, the set of contributors to emergency and disaster preparedness and response is vast and includes a patchwork of methods, cultures, and disciplines that are in some cases themselves struggling to integrate their activities (Kahsai and Kare, 2002; Tang and Fabbri, 2003). In addition to being multidisciplinary, the field of emergency and disaster preparedness and response is undergoing change toward increased professionalization and an all-hazards3 approach, and is evaluating its assumptions and modes of practice, as discussed elsewhere in this report (Alexander, 2003; NRC, 2003).
The integration of a relative newcomer into the large and complex field of emergency and disaster preparedness and response presents challenges and tensions. Disasters require rapid decisions and quick action, which may bring about cross-jurisdictional conflicts, professional differences, and questions about authority, expertise, and the appropriate chain of command.
In its fifth report (IOM, 2003a), the committee discussed at some length the importance of close collaboration between the public health and health care communities, from the level of federal agencies such as HRSA and CDC, to local public health agencies and their health care counterparts (health care organizations, hospitals, private providers, long-term care facilities, etc.). Previous reports by this committee also have called for public health and health care organizations and workers to coordinate and col-