ends when the immediate event subsides. The disaster response begins when the event occurs and ends when acute disaster response services are no longer needed. Disaster recovery also begins with the disaster response and continues until the affected area is returned to the pre-event condition. Disaster planning – The act of devising a methodology for dealing with a disaster event, especially one with the potential to occur suddenly and cause great injury and/or loss of life, damage and hardship. Disaster planning occurs during the disaster interphase. Disaster preparation – The act of practicing and implementing the plan for dealing with a disaster event before an event occurs, especially one with the potential to occur suddenly and cause great injury and/or loss of life, damage and hardship. Disaster preparation occurs during the disaster interphase. Disaster recovery – The restoration or return to the former or better state or condition proceeding a disaster event (i.e., status quo ante, the state of affairs that existed previously). Disaster recovery is the fourth phase of the disaster life cycle. Disaster response – The ability to answer the intense challenges posed by a disaster event. Disaster response is the third phase of the disaster life cycle. Medical contingency planning – The act of devising a methodology for meeting the medical requirements of a population affected by a disaster event. Medical surge – An influx of patients (physical casualties and psychological casualties), bystanders, visitors, family members, media and individuals searching for the missing who present to a hospital or healthcare facility for treatment, information and/or shelter as a result of a disaster. Surge capacity – The ability to manage a sudden, unexpected increase in patient volume that would otherwise severely challenge or exceed the current capacity of the health care system. Medical triage – The separation of patients based on severity of injury or illness in light of available resources. Psychosocial triage – The separation of patients based on the severity of psychological injury or impact in light of available resources. History The term "disaster medicine" first appeared in the medical lexicon in the post-World War II era. Although coined by former and current military physicians who had served in World War II, the term grow out of a concern for the need to care for military casualties, or nuclear holocaust victims, but out of the need to provide care to the survivors of natural disasters and