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Discovery Branch

Standards Used in Metadata Management Program

Descriptive Cataloging Standards

RDA: Resource Description and Access serves as the current authority for descriptive cataloging at NLM. These rules are supplemented by the LC-PCC Policy Statements which appear in the RDA Toolkit. Bibliographic records are formatted according to MARC21 Format for Bibliographic Data. RDA has replaced the Anglo-American Cataloging Rules, 2nd ed. (AACR2) as of March 31, 2013.

Personal and corporate access points appearing in most cataloging records follow either AACR2 rules or RDA guidelines. Some records were cataloged prior to the adoption of AACR2 and thus, the headings used may reflect earlier cataloging practices. NLM has been submitting authority records to NACO (Name Authority Cooperative Program of the PCC) for its English language material since 1985. Beginning in March 2012, NLM has been submitting all authority records to NACO. The authority records are formatted according to MARC21 Format for Authority Data.

NLM applies multi-level description in the cataloging of monographs: full level descriptive cataloging, Bibliographic Standard Record (BSR)-level cataloging following the standards promulgated by the Program for Cooperative Cataloging (PCC), and NLM's minimal level or "Limited cataloging." Serials are cataloged following the CONSER Standard Record (CSR) guidelines or NLM’s minimal level cataloging standard. Details of the various levels of description used at NLM in the cataloging of monographs and serials are documented in NLM Cataloging Section: Definition of Cataloging Levels. Details of the various levels of description used at NLM in the cataloging of monographs and serials are documented in NLM Cataloging Section: Definition of Cataloging Levels.

Subject Cataloging Standards


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Last Reviewed: April 2, 2024