Methodological issues relate to normative adolescent sexual behavior, defining the issue to be studied, models of deviance, assessment of deviance (via interview, deviance, assessment of deviance (via interview, questionnaire, and psychological assessment), and difficulties inherent in evaluating treatment strategies. Ideally, evaluative research should use a homogeneous sample, standardized and multiple outcome measures, control or comparison groups, and adequate followup. Ethical issues in such research include confidentiality concerns (disclosure of previously unknown information to the criminal justice system or parents) and those related to mandated treatment. Despite these constraints, methods can be devised that permit the study of factors that instigate and maintain deviant sexual arousal and ways of preventing it. 32 references.