National Union Catalog of Manuscript Collections

n. (NUCMC, abbr.)A collection of descriptions of manuscript collections, archives, and oral history materials held by eligible archival and manuscript repositories throughout the United States and its territories.The program within the Library of Congress that oversees production of the catalog and supports access to the database.


Commonly pronounced nuck-muck. Originally issued as printed volumes starting in 1961, NUCMC began entering descriptions into the Research Libraries Group (RLG) database in 1986. Many of those records are duplicated in the OCLC National Union Catalog. The print series was discontinued after volume 29 in 1993. NUCMC currently functions as a "virtual" catalog, providing free searching at its website of cataloging in the RLIN and OCLC databases describing archivally controlled materials. See


LoC 2002 The National Union Catalog of Manuscript Collections (NUCMC) is a free-of-charge cooperative cataloging program operated by the Library of Congress. On the basis of cataloging data supplied by eligible repositories, NUCMC catalogers create MARC (Machine Readable Cataloging) bibliographic records in the RLG (Research Libraries Group) data base, a national-level database, describe collections held by participants, and establish pertinent name and subject authority headings. Descriptions and locations of the material are then available to researchers throughout the United States and around the world.