Until recently, patients suffering from both a psychotic disorder and a post-traumatic stress disorder (ptsd) were hardly ever treated for their ptsd. Many clinicians considered that the reliving of the trauma during treatment could increase the risk of psychotic decompensation. We describe a trauma-focused cognitive behavioural therapy that was used to treat a 43-year-old patient diagnosed with both schizoaffective disorder and comorbid ptsd. After five sessions the patient no longer experienced ptsd symptoms.