Aging has emerged as an important area of social concern, first in industrialized countries and now in the less developed regions of the world. Demographic changes caused by increased life expectancy and declines in birth rates have resulted in a dramatic shift, with the proportion of older people increasing rapidly to form a substantial segment of the population. This demographic reality and the growing awareness of the aged as a definable social group have led to gerontology developing as a multidisciplinary endeavor. Initially, much gerontological research was biologically oriented, and only recently has its interaction with psychosocial factors, as they influence health and behavior, become a focus of concentrated attention. While sexological research in the field of aging has made significant advances, moving from the descriptive and epidemiological to the physiological and more recently to the biomedical and clinical, it has yet to fully integrate psychosocial perspectives in its studies. A review of data points to several methodological problems, not all limited to sexological studies, that need to be considered when interpreting the results. Much of the research is cross-sectional in design, confounding the effects of aging with differences in the attitudes, values, and behavior that characterized the different age cohorts as they grew up. Longitudinal studies, on the other hand, are undermined by selective attrition, biasing the results in the direction of the healthier, stable, and cooperative participants. Conclusions are frequently drawn from small, unrepresentative and nonrandom samples of white, middleclass and well-educated volunteers who are probably more liberal in their sexual attitudes than their counterparts who decline to participate in sexological research.