This study explored the effectiveness of a psychoeducational family intervention for schizophrenia on patients' clinical status and disability and relatives' burden and perceived support. The study has been carried out in 17 mental health centres. In each of them, 2 professionals were trained in a psychoeducational intervention and applied it for six months with families of users with schizophrenia. At baseline and six months later, patients' clinical status and disability, and relatives' burden, social network and professional support were assessed by validated tools. Of the seventy-one recruited families, 48 (68%) completed the intervention. At six months, a significant improvement was found in patients' clinical status and social functioning, as well as in relatives' burden and social and professional support. In particular, the percentage of patients with poor or very poor global social functioning dropped from 50% to 27% at six months. Forty percent of patients and 45% of relatives reported a significant improvement in their social contacts over the intervention period. The results of this study confirm the hypothesis that psychoeducational family interventions may have a significant effect on social outcome and family burden in schizophrenia when provided in routine conditions.