On the premise that researchers, practitioners, and policy makers lack an extensive and systematic examination of the concerns of the aging, this monograph examines American social issues as a context for a functional definition of aging and a taxonomy for use in conducting research. Issues are examined with regard to aging and work in four areas of American society: waste of human resources, retirement, mental health and education. Health care and financial independence emerge as major concerns. Focus is on the context of social welfare versus self-help approaches and the need for more precise ways to describe the population. A functional definition is proposed in which an aging index is derived from measures of physical status, psychological well-being, economic stability, socialization, life satisfaction, and chance factors. A taxonomy of work and aging is then outlined which presents a systematic way to identify and state researchable questions concerning various groupings of older persons and the work conditions which may provide available work options for them. The taxonomy assumes that people experience the aging process differently, that the aging process is developmental, and that people operate at functionally different levels of ability and efficiency, and that people regardless of age, at different points in time and for different reasons, have needs for paid and/or unpaid work activities and associations. A final section presents implications for federal policy on aging, retirement, mental health, and education calling for major research efforts to bring clarity to the issues raised. (JT)