Despite the omnipresence of threatening experiences, the human species displays remarkable resilience in adaptation. This has been significantly neglected until recent years in both clinical observation and systematic research. The present paper summarizes some information on coping behavior under stress and suggests the potential utility of such information in the practice of medicine. The information is drawn from studies dealing with situations of life-threatening illness and injury (severe burns, severe poliomyelitis, and childhood leukemia). Severe physical impairment, especially if it occurs suddenly and without warning, is an extreme test of coping capacities. Study of parents of leukemic patients elucidated reactions similar to those observed in studies of burn and polio patients. Coping strategies useful to persons of various ages, both sexes, and different socioeconomic backgrounds in facing a variety of tasks in several stressful situations of life-threatening significance are described.