Systematic data concerning sexual, marital and social experience were obtained by structured interviews with males taking part in the Baltimore Longitudinal Study of Aging. In analysis 188 subjects aged 60-79 and married at interview were divided into thirds according to quantity of sexual activity reported for the preceding year. Subjective and behavioral variables were then related to subjects classified as least active, moderately active and most active sexually in order to identify factors affecting level of sexual functioning at these ages. Major correlates of being sexually most active were: a strong commitment to religious values, early farm residence, high socio-economic status, more abundant sexual activity during the earlier years of life, continued erotic responsiveness to visual stimuli, and unimpaired potency. Future plans are to relate variables derived from these interviews to such diagnostic entities as coronary artery disease, hyperlipidemia and other disabilities. BIBLIOGRAPHIC REFERENCE: Martin, C.E. Sexual Activity in the Aging Male. In: Money, J. and Masaph, H. (Eds.): Handbook on Sexology, New York, Elsevier/North Holland, 1977, pp. 813-824.