Cognitive adaptation training (CAT) targets the adaptive behaviour of patients with schizophrenia and has shown promising results regarding the social aspects of psychosocial treatment. As yet, no reports have appeared on the use of CAT in combination with assertive community treatment (ACT). Our purpose was to evaluate the effect of CAT in comparison with ACT, focusing on social functions (primary outcome), symptoms, relapse, re-hospitalisation, and quality of life of outpatients with schizophrenia.