Case material is used to demonstrate the difficulties of differential diagnosis in schizophrenia. The authors are involved in making such a differential in purely descriptive terms, with necessarily more subjective than dynamic formulations, and without such concepts as projection, object relation, and reality testing. They recognize the fact that Kasanin, Zilboorg, and Sullivan used the terms 'neurotic schizophrenia', 'ambulatory schizophrenia' and 'incipient schizophrenia' respectively and that these terms may describe the same group of cases which they now wish to designate by 'chronic incipient schizophrenia'.