Based on methodology similar to that used in international studies, the calculation of costs was carried out for three cohorts of patients: schizophrenics, other psychotics and non-psychotics, taking into account the parameters of sex, age, professional employment/unemployment. Attention is paid particularly to: the preponderance of indirect costs over direct costs, the much higher level of costs for psychotic patients and amongst these above all of schizophrenics, and significant differences in this last group with regard to sex and age. As far as direct costs are concerned, no substitution of hospital costs by outpatient costs is noted; on the contrary, the cumulative effect of these two constituent parts is marked among the three cohorts no matter what parameters of analysis of data are used.