The currently dominant multi-factorial explanations of sex offending have been reflected in the widespread adoption of cognitive-behavioral group-work methods in which treatment foci are those attitudes, beliefs, cognitions, and behaviors believed to contribute to the maintenance of sexually abusive practices. Community-based programs have increased in Great Britain during this decade, with 97 percent of regional probation services now providing for sex offender treatment; however, these relatively recent and dramatic developments in practice have largely occurred outside of a framework of rigorous planning and evaluation. Although small-scale (in-house) research may indicate something about the success or failures of individual programs, the large-scale projects conducted by independent researchers provide evidence of the impact of cognitive-behavioral group work on recidivism and offense-related psychological variables. Such research has the potential to assist policy-makers and to aid managers and practitioners in the development of effective treatment programs. This paper notes that such evaluation studies conducted thus far provide support for the effectiveness of cognitive-behavioral treatment in reducing recidivism in some sex offenders and its effectiveness in modifying attitudes and cognitions associated with the sexual abuse of children. This does not, however, preclude the need for further evaluations, since programs will differ in content, length, client base, treatment integrity, and worker expertise. 54 references