A disaster is a serious disruption, occurring over a relatively short time, of the functioning of a community or a society involving widespread human, material, economic or environmental loss and impacts, which exceeds the ability of the affected community or society to cope using its own resources. The disasters can be classified into two types based on their form of occurrence. These are natural disasters and man-made disasters. Disaster management can be defined as the organization and management of resources and responsibilities for dealing with all humanitarian aspects of emergencies, in particular preparedness, response and recovery in order to lessen the impact of disasters. Aims, principles, and phases of disaster management are defined in this chapter. Disaster preparedness is focused on preparing equipments and procedures for use when a disaster occurs. Disaster impact is the result of occurrence of disaster and most injuries sustained during impact. Rehabilitation is final phase in disaster that leads to restoration of pre-disaster conditions. Salient features of disaster management are also mentioned in this chapter.