Presents data concerning 2548 urban Lebanese psychiatric patients. A statistically significant association was found between class position as determined by estimated family income and the prevalence of psychiatric disorders. Ss were over represented in the lower class and this relationship was shown to persist when the factors of age, sex, marital status, and religion were controlled. A significant association was shown between class position and types of psychiatric disorders. Neurotic disorders were over represented in the upper class and psychotic disorders in the lower class. Class differences within the constituent diagnostic types in these 2 larger categories are discussed and preliminary results from the analysis of the components of total prevalence are reported.