Research indicates a move toward more cognitive features in assessment. In particular, one interpretation of the evidence to date suggests that phallometry has been overvalued and that considerable work remains to be done on psychometric aspects of erectile measurement. Treatment has also moved in a more cognitive direction, but the addition of a relapse prevention approach has been the most significant innovation. A focus on treating juveniles has been a major development over the past 10 years. Theory development is accelerating, but more emphasis is needed on developing and refining specific constructs rather than on elaborating broad explanatory theories. Sex offender treatment is examined in terms of assessment, the development of social skills, cognitive processes, and offender personality profiles and histories. Specific aspects of sex offender treatment programs are addressed that focus on denial and minimization, victim empathy and harm, attitudes and beliefs, fantasies, and relapse prevention. 150 references