The thesis of this paper is that a reintroduction of the concepts of psychosis derived from French psychiatry would be of value in terms of clinical precision, research and treatment. The relatively few diagnostic entities employed in North America in the classification of psychoses other than depressive and organic is contrasted with a more extended French nosological system. The demonstrated usefulness of the precise classification of depressive syndromes suggests that similar discrimination applied to other psychoses would be a promising area for research.