The report examines patron characteristics and use patterns of the New York Public Library Research Libraries. A general user survey was conducted as well as surveys of the use of the Photographic Service, Special Collections, Special Study Areas, and Reference Correspondence Service. Chapter I is a summary of principal findings and conclusions. Chapter II covers the status, academic affiliation, occupational fields, educational level, and place of residence and employment of the patrons. Chapter III discusses the use of the Research Libraries including divisions used, frequency and intensity of use, purpose of visits to the Research Libraries, materials sought and used, libraries used previously, and usefulness of resources. Chapter IV covers the effects of patron characteristics on the use of the Research Libraries. Projections for future use are given in Chapter V. The appendices include extensive descriptions of the five surveys, copies of the user questionnaires, and a study of seasonal variations in use. (CC)