This chapter discusses intervention issues with a sex offender with intellectual disability. Treatment for inappropriate sexual behavior in men with intellectual disability requires considerable adaptation so that it can be accessible and meaningful. Training is required to understand the way in which treatment should be adapted. There are a number of publications that can assist program developers to organize treatment relevant to people with intellectual disability. There are specific theoretical considerations that incorporate the alternative developmental experiences of people with intellectual disability. The principle theoretical position that has been developed for men with intellectual disability is the counterfeit deviance hypothesis. Quality of life and the good lives model have been germane to work with people with intellectual disability for decades, and this has extended to sex offenders with intellectual disability as a natural process.. Important pretreatment considerations for facilitators include accessibility, use of language, ownership, and motivation. This is particularly relevant to the skills and considerations required for facilitators of treatment programs for this client group. There are specific assessments for sex offenders with intellectual disability, and these require alternative methods of administration. Some of these assessments have been illustrated in the current chapter and the primary consideration for the assessor is that few if any of the offenders will have well developed literacy skills. There are a number of studies showing treatment effectiveness but they lack appropriate experimental control. (PsycINFO Database Record (c) 2019 APA, all rights reserved)