Before 2001, psychiatric care on the island of Mayotte was ensured by missionaries from the Reunion Island. A mental health system has since been gradually installed, although the culture in Mayotte, mixing practicing Muslim women and traditional animists, still leaves a broad place for traditional healers. This paper presents a retrospective study of 1212 psychiatric case reports, aimed at indexing the various psychopathologies according to the CIM 10, on the island of Mayotte between 1998 and 2004. The files, before and after the opening of the mental health centre, were compared with those of the psychiatric diagnoses of the Comorians. The results show an evolution in the chronic pathologies treated in the Comorians: delirious disorders, and the organic, major, mental disorders in the first psychiatric files have given way to depressive episodes and somatoform disorders. Nevertheless, an underlying prevalence of depression and addiction persist. It is interesting to note the reduced number of suicide attempts, far lower than in western countries: one suicide attempt per annum for 375 inhabitants in metropolitan France, whereas, in this study, one suicide attempt in Mayotte was reported for 2504 inhabitants. The cultural characteristics are also taken into account in the discussion of these results. Thus, if there are more demonstrations with somatic expression in the Comorians, related to a stronger implication of the body in situations of psychological faintness: 1.75% of hysterical conversion in the Comorians versus 0.99% in Mayotte, this does not mean a more histrionic personality in this population: 1.8% of Comorians, against 1.98% in Mayotte. The results of this study consolidate the impressions felt by the experts and show the effects of the mental health policy on the island. Thus, the assumption of responsibility of chronic psychotics made it possible to improve their quality of life, and to decrease the number of medical evacuations that decreased from 17 to three, between 2001 and 2004. However, this study also underlined the possible axes of development in this field, namely the assumption of responsibility of psychiatric emergencies with a crisis centre, and the development of a specialized pedopsychiatric assumption of responsibility. Indeed, in the first six months of 2004, 35% of the patients were 0-20 year-old.