Information about risks should be complemented by problemsolving programs designed to counteract social inhibitions on the use of contraceptives and environmental manipulations designed to increase access to condoms. Market-based regulatory strategies show some potential to decrease needle-sharing among drug abusers. There is a compelling need for a large behavioral research initiative to develop a body of knowledge necessary for the prevention of HIV infection among adolescents. Social inhibitions about studying 'adult' behaviors among juveniles should be overcome, and legal protection of the privacy of juvenile research participants should be expanded. Research should proceed in four broad areas. First, there is a need for descriptive studies about adolescent sexual behaviors, intravenous drug use, and other risk-taking behaviors. Research on basic developmental processes should be expanded, particularly in the area of cognitive and social factors that affect risk perception. Attention also should be given to the development of sexual identity and its relation to the initiation of certain sexual behaviors. Field experiments are needed to examine the effects of prevention strategies among particular groups of adolescents. Finally, longitudinal studies are needed in each of there previous areas to identify precipitants of risky behavior, factors in attitudinal and behavioral modification, and problems in the maintenance of behavior change. 41 references. (Author abstract modified)