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Discovery Branch

The Discovery Branch, User Services and Collection Division (USCD), National Library of Medicine, is responsible for the selection, acquisition, and cataloging of all materials for the NLM modern collection. Discover Branch coordinates technical services programs and projects with the library community including other national and research libraries in the U.S. and abroad, several library associations, and other Government and non-Government organizations.

Office of the Chief

The Discovery Branch Office of the Chief (OC) focuses on the branch information of planning and administration, budgeting, policy, and collaborative activities. The OC leads the periodic review and revision of the Collection Development Guidelines of the National Library of Medicine, oversees the PubMed Central (PMC) Journal Review Program, and approves selection of PMC journals.

Metadata Management Program (MMP)

The Metadata Management Program (MMP) is responsible for review and development of cataloging policies for descriptive and subject cataloging and classification of modern print, audiovisual, and electronic resources acquired for the NLM collection. The Section creates and maintains the bibliographic records resident in NLM's public access catalogs, the LocatorPlus Catalog and the NLM Catalog. The LocatorPlus Catalog contains records in the MARC 21 format and displays holdings and item availability. The NLM Catalog uses the NCBI Entrez retrieval system and records are structured in a locally defined XML format. See Bibliographic Records Accessible on the Web for additional information.

NLM bibliographic records are available via ftp in MARC 21 format or in XML format. For further information, see NLM Data Distribution Program.

The MMP Program maintains and develops the NLM Classification, a scheme for the shelf arrangement of medical literature in libraries. The Section also maintains NLM's internal authority file used in the creation of bibliographic records, including over 1.2 million name, title, and subject heading records and assigns the NLM title abbreviations for indexed serials.

For further information, see the Metadata Management Program (MMP) Home Page.

Data Applications and Systems Program (DAS)

The Data Applications and Systems Program (DAS) manages the bibliographic and digital library systems used to support the Division’s collection development, acquisitions, licensing, electronic resources management, and cataloging operations. These systems also support a broad range of NLM services including collection management, circulation, preservation, indexing, and access to the NLM collection.

The DAS Program coordinates the maintenance, development, testing, training, and documentation for numerous systems, including the NLM Library Services Platform, online public access catalog LocatorPlus Catalog, and systems to support NLM selection work and indexing and citation creation activities. The DAS Program leads the development of NLM’s repository, Digital Collections.

DAS Program staff evaluate and test NLM desktop software applications and provide first-level hardware and software desktop support for the Discovery Branch.

For general information on NLM services, contact:

National Library of Medicine
Customer Service
8600 Rockville Pike
Bethesda, MD 20894
Telephone: 1-888-FINDNLM (1-888-346-3656)
email: //
NLM Customer Service Form at Contact NLM

Last Reviewed: April 2, 2024