The authors base their report on the case histories of 50 psychiatric in-patients, all Moslem French immigrants. The common characteristics are: 1. the absence of mental illness before immigration and throughout the first years in France; 2. a stay of at least one year in France. Five tables illustrate these case histories. Once again the question of immigration and in particular that concerning Algerian Moslems who chose French nationality in 1962 has been taken up. Certain problems concerning the failure of integration of immigrants have been highlighted. A bibliography comprising 24 books or articles completes this work.