Objectives: To explore the literature through a systematic search to assess the effectiveness of mutual support groups for family caregivers of people with schizophrenia and other psychotic disorders.Methods: This review of the research literature was based on the procedures suggested by the National Health Service Centre for Reviews and Dissemination (2001) Report Number 4 in the UK. A combined free-text and thesaurus approach was used to search relevant research studies within electronic databases, including Medline, Embase, CINAHL, OVID full-text, PsycINFO, the Cochrane Library, the British Nursing Index, the NHS National Research register, and System for Info on Grey literature for the period 1980-2007. Reference lists of all retrieved literature were also searched to identify studies that may have been missed. Twenty-five research studies were selected for inclusion in the analysis on the basis that they were either family-led or professional-facilitated support group programmes for family caregivers of people with schizophrenia or other psychotic disorders.Results: The review identified that most studies on this group programme used qualitative, exploratory cross-sectional surveys and quasi-experimental study designs (n= 19); six were experimental studies or randomised controlled trials. There were only a few small-scale, singlecentre controlled trials with the findings supporting the significant positive effects of mutual support groups on families' and patients' psychosocial well-being. A number of nonexperimental studies conducted in Western countries reported benefits of group participation up to one year, such as increased knowledge about the illness, reduced burden and distress, and enhanced coping ability and social support. However, many of these studies lacked rigorous control and did not use standardised and valid instruments as outcome measures or schedule follow-up to examine the long-term effects of support groups on families and/or patients. This is the Pre-Published Version.2 Conclusions: With increasing recognition of benefits from mutual support, this review highlights the dearth of evidence for the effects and active ingredients of mutual support groups.Mutual support may have significant impacts on long-term psychosocial and nursing interventions for both patients with severe mental illness and their families in community mental health care. Further research is recommended to investigate the therapeutic components and effects of mutual support groups for family caregivers of people with schizophrenia and psychotic disorders across cultures.