Purpose of review This paper focuses on reviews and reports of psychological interventions for individuals with dual diagnosis (intellectual disability and mental health problems) from March 2003 to March 2004. Recent findings Two reviews that evaluated the psychological treatment outcome literature, but spanned different time periods, arrived at different conclusions regarding the progress of the research efforts to date. They agreed, however, on many of the limitations of the research. Case-studies of psychological treatment of aggression, elective mutism, dog phobia, bereavement, borderline personality disorder, and sleep problems appeared in the literature. Intervention techniques represented behavioral, cognitive behavioral, psychodynamic, and psycho-educational approaches. One group intervention for women's health combined psycho-educational and coping skills training. When ongoing service delivery in the community was examined, interventions were found to be non-specific. A report that detailed characteristics of treatment provided in the community was an impetus for the promulgation of standards of care in one region. A measure of sex-offending cognitions was developed and preliminary validation efforts completed. There continues to be a need for assessment instruments designed for persons with intellectual disability. The publication of a psychiatric diagnostic classification system for persons with intellectual disability may improve the reliability of diagnoses, which, in turn, will improve the quality of psychotherapy outcome research. Summary Depending on the review period and the evaluation criteria, authors proclaimed the glass either half empty or half full, that is, some progress or no progress being made in psychological interventions with persons with intellectual disability. Case-studies continue to dominate the literature and offer considerable variety in terms of the problems treated and the intervention techniques used. A significant development in psychiatric diagnosis (Diagnostic Criteria for Psychiatric Disorder for Use with Adults with Learning Disabilities) will guide future progress in intellectual disability research. Continued advances are also needed in assessment.