A theory of organizing and role enactment during the emergency period of disaster will be refined and field tested over a two-year period in this project. Organizing has been observed in earlier work by the principal investigator as interrelationships among four core elements: domains, tasks, human and material resources, and activities. The four elements have proved to be useful for describing how organization is improvised in communities threatened by earthquakes, floods, hurricanes, and tornadoes. The data bases will be archival data on earlier disasters and primary data on two disaster events collected during the current project. The findings will yield principles of emergency management that are both historically based and contemporary.