One argument for treating sex offenders rests on the proposition that it is possible to modify a sex offender's behavior by treatment through individual or group therapy or as part of a therapeutic regime. The second strand in the case for treatment recognizes that sex offending is a wide-scale social phenomenon, the causes of which are to be found in society's values and practices, as well as in the psychopathology of individual offenders. Third, many sex offenders have themselves, in their own childhoods, been the victims of precisely the kinds of sexual offenses they have committed against others. Finally, there is a case for treating sex offenders, not so much for their own benefit, but because it may meet the needs of the victims. The author concludes that the case for treatment is limited if taken purely in terms of modifying the behavior of current offenders; however, presenting the results in terms of "offenses prevented" by treatment, the results look more reasonable. If a cost-benefit analysis is conducted on the results, comparing the cost of psychologists' salary and expenses involved with savings on the costs of imprisonment, even a conservative analysis shows that the work more than pays for itself. 19 references