There exists in the literature a group of nonorganic psychoses which appear to have no obvious relationship to either schizophrenia or affective illness. Diagnostic terminology to classify these atypical psychoses has been varied, although features in common can be identified. For example, they often are associated with antecedent personality problems, acute onset, florid and mixed symptomatology, brief duration, and full remission with a return to premorbid level of functioning. Case material reflecting these types of psychoses is presented here, and is discussed with reference to the nosologic status of these atypical psychoses.