Résumé : Purpose. - Adverse social experiences are frequently invoked to explain the higher rate of psychosis among migrant groups. The aim of the present study was to establish the socio-environmental factors distinguishing migrant psychotic patients from autochthonous patients. Subjects and method. - We conducted a cross-sectional survey involving 341 migrant psychotic patients matched for age and gender with 341 autochthonous psychotic patients. Results. - Migrant patients lived more often with their parental family, were less often enrolled with a referral psychiatrist, presented a lower rate of employment, a lower percentage of alcohol misuse and of suicide attempts. Discussion. - Our findings add to the growing body of results showing that more attention needs to be focused on socio-environmental variables in psychosis research. However, several limitations have to be taken into account, particularly with regard to selection biases and age of onset of the psychotic illness. Conclusion. - Our results are compatible with the hypothesis that unemployment is a contributing factor in the risk for psychosis among migrant groups. Migrants' families are an important keystone in the mental health care process of their sick relatives. Our service models need to be adapted with the aim to make the treatment easier for migrant patients. © 2004 Elsevier SAS. All rights reserved.