Aging is the third great antecedent to all disease, along with genetic factors and the environment. Yet, the role of aging in the genesis of the conditions of old age constitutes relatively new territory that has not been adequately explored in terms of education, the health care system, and research. A commitment to these areas was made in 1982 when the Mount Sinai Medical Center established the nation's first and only medical school department of geriatrics--the Gerald and May Ellen Ritter Department of Geriatrics and Adult Development. Recognizing that aging of the population constituted a major global public health challenge, leaders of the medical center turned to Robert N. Butler, MD, who was then director of the National Institute on Aging, for guidance in setting up an institute of gerontology and geriatrics. Because only a full-fledged academic department would have a claim on resources, curriculum, and clerkship time, Dr Butler recommended that such a department be developed at Mount Sinai. The Ritter Department of Geriatrics and Adult Development emphasized the wide scope of this new discipline through educational programs, clinical services, health policy studies, and research projects.