This issue of the Archives reports on the preliminary results of a comprehensive collaborative effort by scientists at the National Institute of Mental Health and in the field to assess the prevalence of mental disorders in the United States. The "survey" is far more than a simple census. It is a landmark in the development of American contributions to the psychiatric knowledge base. This is so in several senses.
The forthcoming data of the NIMH Epidemiological Catchment Area program (ECA) surely will serve as a kind of topographic map, a background charting relative peaks and valleys and their specific contents. Against this descriptive frame, a range of special studies and more focused analytic ones can be generated and compared. Crosscultural study, samples of patients and families drawn from clinical practice or from various registers and longitudinal study populations can be matched against the topographic coordinates or anchor points that