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Chapter 11. Library of Congress Subject Headings

Chapter Outline

  • Introduction

  • Subject Authority Records

  • Main Headings: Functions, Types, Syntax, and Semantics

  • Subdivisions

  • Cross-References

  • Assigning LC Subject Headings: Precoordination vs. Postcoordination

  • Assigning LC Subject Headings: Special Materials

  • Subject Headings for Children's Literature

Key Takeaways

The Library of Congress Subject Headings (LCSH) subject vocabulary is covered in this chapter.

LCSH & availability

Originally developed for use by the Library of Congress (LC), the Library of Congress Subject Headings (LCSH) is a set of headings that are authorized for use as subject access points in bibliographic records. LCSH is a general vocabulary, meaning it does not specialize in any particular disciple or domain. Most libraries in the USA and many across the world use the LCSH and their main subject-controlled vocabulary. 

The majority of the terms in the LCSH vocabulary are topical subject headings but other types, such as authorized access points for place, person, family, and corporate names can be used in the construction of subject headings.

The complete and most updated LCSH is available through the LC's Classification Web subscription tool. PDFs of the LCSH (not always the latest version) and LC authority records of established headings and subdivisions are available for free via the LC website ( 


The structure or the organization of the vocabulary is in alphabetical order. Equivalence, hierarchical, and associative relationships between subjects are indicated with the use of cross reference, using the notations of UF (used for) and USE for the hierarchical relationships, BT (broader term) and NT (narrower term) for the hierarchical relationships, and RT (related term) for all associative relationships.

In LCSH authority records, these relationships are indicated by the respective MARC authority fields and relationship codes.


LCSH is a highly pre-coordinated vocabulary. Established combinations exist in the vocabulary but the system also allows the cataloger to construct numerous combinations of headings and subdivisions, following the Subject Headings Manual guidelines and instructions under existing main headings and subdivisions. This allows for the expression of very complex topics into one string but is also seen as a challenge for users when interacting with the library catalog.


As a pre-coordinated system, LCSH uses different types of subdivisions that can be attached to a main heading for the expression of complex topics. These types are reflecting different facts, such as topical, geographical, chronological, and form.

Free-floating subdivisions are a group of common subdivisions (topical & form) that may be used without prior authorization under a particular subject or name heading where applicable and appropriate.

Pattern headings

Certain subdivisions, topical or form, are common in a particular subject field. These subdivisions are listed under a chosen heading in the category instead of repeating them under each heading within the same category. The chosen heading serves as a pattern heading of subdivisions for all other headings in that category.


The Subject Headings Manual (SHM) provides guidelines to use the LCSH. Originally developed as an in-house procedure manual, it became a tool for other libraries — in fact — most users of the SHM are now outside the LC. The manual includes explanations of subject cataloging policies, procedures, and practices in proposing new headings to be included in LCSH and assigning LCSH subject headings to bibliographic records for subject representation and access.

Children's subject headings 

The Children’s Subject Headings include alternate headings for use with children’s materials. These headings are not in LCSH and are different in form from those found in LCSH.

Chapter References/Notes

  1. Library of Congress, Catalog Division. (1910–1914). Subject headings used in the dictionary catalogues of the Library of Congress. Washington, DC: Government Printing Office, Library Branch.

  2. Library of Congress, Subject Cataloging Division. (1984). Subject cataloging manual: Subject headings (prelim. ed.). Washington, DC: Library of Congress.

  3. Library of Congress. Policy and Standards Division. (2008). Subject headings manual. Washington, DC: Library of Congress. Retrieved from

  4. Chan, L. M. (1990). Library of Congress subject headings: Principles of structure and policies for supplication. Washington, DC: Library of Congress.

  5. Subject Headings Manual, H690.

  6. Subject Headings Manual, H690.

  7. Chan, 1990, p. 17.

  8. Chan, 1990. p. 27.

  9. Library of Congress, Cataloging Policy and Support Office. (1989). Free-floating subdivisions: An alphabetical index. Washington, DC: Library of Congress, Cataloging Distribution Service.

  10. Subject Headings Manual, H1095.

  11. Subject Headings Manual, H1100, H1103, H1105, H1110, H1140, H1145.5.

  12. Subject Headings Manual, H830.

  13. Svenonius, E. (1990). Design of controlled vocabularies. In A. Kent (Ed.), Encyclopedia of library and information science (Vol. 45, Supp. 10, p. 88). New York, NY: Marcel Dekker.

  14. Subject Headings Manual, H1520.

  15. Subject Headings Manual, H1155.2, H1155.6, H1155.8.

  16. Association for Library Collections & Technical Services, Cataloging and Classification Section, Subject Analysis Committee, Subcommittee on the Revision of the Guidelines on Subject Access to Individual Works of Fiction. (2000). Guidelines on subject access to individual works of fiction, drama, etc. (2nd ed.). Chicago, IL: American Library Association.

  17. Subject Headings Manual, H1330.

  18. Subject Headings Manual, H1110.


Additional Readings

Here, you will find readings specific to the contents of this chapter.

You may find more readings about similar topics on the Cataloging and Classification Web Resources page

Library of Congress Subject Headings (LCSH)​ Resources

LCSH Proposals and Lists​



Subject Heading Manual (SHM)
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