Background: Anxiety disorders have high prevalence in people with intellectual disabilities. In populations without intellectual disabilities, cognitive behavioural therapy is a first line psychological therapy for these presentations. There is no existing review of the range of methods and outcomes from intervention studies in this area. Method: A systematic review was carried out following guidance in the Cochrane handbook for systematic reviews of interventions. Results: Nineteen studies were identified. The majority of reports were descriptive case studies; the most frequently described presentations were non-specific anxiety disorders and post-traumatic stress disorder; the most frequently described cognitive techniques were psycho-education and interventions directly aimed at thoughts and beliefs and most studies reported positive outcomes, although the better controlled studies tended to report less comprehensive impacts. Conclusions: A range of presentations have been described although the area is still at a primarily descriptive stage. We discuss intervention structures and approaches that require further research.