Mental health workers need to be members of the disaster response team from the onset and take mental health services to survivors. A range of psychological and emotional responses to disaster are normal and should not be “pathologized” or “medicalized”. This chapter helps the reader to identify the psychosocial effects likely to occur in various types of disasters, identify the elements of a community impact and resource assessment, and describe the normal reactions of children and adults to disaster. It provides brief description on bioterrorism and toxic exposures, community impact and resource assessment, normal reactions to abnormal events, special needs popluations, and community reactions and responses. The psychosocial impact of a disaster and the resources that will be needed to respond to the disaster can be estimated based on data from past experiences with a variety of natural and man-made disasters.