One of the difficulties in diagnosing sex offenders is that many have multiple paraphilias (perversions). Further research needs to be done on the development of adolescent sex offender typologies, since there is current disagreement among researchers about whether or not deviant adolescent sexual behavior is normal experimentation. Etiological theories of sexual deviance are based in psychological and social learning theory. Criminological research focuses on the prediction of recidivism among sex offenders. Because of the frequent use of denial by sex offenders, assessment must draw from various sources, including clinical interviews, paper-and-pencil tests, psychophysiologic assessment, victim reports, family reports, and criminal justice information. The treatment format at the Sexual Behavior Clinic of the New York State Psychiatric Institute involves many components, including satiation, covert sensitization, social skills training, assertiveness skills training, cognitive restructuring, sexual education, and the treatment of sexual dysfunction. 58 references.