Purpose of review: This review assesses the impact of recent research on the field of offenders with intellectual disabilities. Research includes work on prevalence, developments in appropriate assessments and investigations into the effectiveness of treatment procedures. Recent findings: Methodological difficulties continued to beset studies on prevalence, with estimates ranging between 2 and 10% of the offender population having intellectual disabilities. Research on risk assessment has developed quickly in the last 7 years and current studies establish both the framework for assessment and new instruments that have been shown to predict offending incidents. There have been a number of promising studies on sex offender treatment and on the treatment of issues related to general offending. These studies continue to evaluate treatment progress in terms of improvements in behaviour, cognitive distortions and reductions of offending. One notable study had targeted reductions in sexual deviancy. With two exceptions, the main drawback in treatment studies continues to be the lack of control conditions. Summary: These research studies will aid clinicians in the implementation of the assessment reviews and treatment programs for offenders with intellectual disabilities.