Traditional aging studies have seen life's later years as a time of inevitable biological and social decline. Psychological decline might also be expected, but this is not true for most older people, according to epidemiologic studies. Thus, we must ask: Why is aging not as emotionally threatening as might be expected? Why do some older people do better than others? How should medicine address these issues? It is only possible to understand the successful emotional aging of most elders if the customary diathesis-stress model is supplemented by a developmental perspective. Expectations as well as capacities diminish with aging. This means that subjective health appears more tightly linked with morale than objective health. Some older people experience recurrence of mental disorders (for example, major depression) first present earlier in life. Others experience new disorders such as minor depression in response to biological or social losses. As geriatric medicine comes to increasingly focus on chronic disease, attention to morale is an important strategy for maximizing quality of life. Physicians will need improved skills in the detection and treatment of problems in morale if they are to provide optimum care for their older patients.