The Research Diagnostic Criteria (RCD) and the Schedule for Affective Disorders and Schizophrenia (SADS) were developed in the mid-1970s by researchers at the New York State Psychiatric Institute and at Columbia University. This article shows their clinical and research interests. The authors of the french translations, compare them to the recent DSM-III. These criteria represent a widely used nosologic system for clinical research in psychiatry. The SADS was developed in an effort to provide research investigators with a clinical procedure which reduce information variance in both diagnostic and descriptive evaluations of subjects.