1. Library of Congress Subject Headings (LCSH)
Thomas Meehan
Head of Cataloguing and Metadata
UCL Library Services

2. Purpose of LCSH
Subject access for catalogue records across broad range of subjects.
Primarily to serve the U.S. Library of Congress (since 1898).
However, far more widely adopted and suggestions can be made via SACO (UCL not a member).
In practice tied closely to the LC Name Authorities.
Coverage decided by “literary warrant” rather than a comprehensive treatment of human knowledge.
Originally printed in the Red Books.

3. General Structure Not a facetted scheme!
Not a nicely structured facetted thesaurus like MeSH, the IOE Thesaurus.
Changes are made over time and take time to carry out.
Literary warrant.
Not ideal, but does make it a lot more flexible.

4. Structure and formatting 1
Preferred term UF BT RT SA NT Non preferred term USE Preferred term
Preferred term Used For Broader Term Related Term See Also Narrower Term Non preferred term Use Preferred term
The standard layout of a subject entry. On the left is the abbreviated terms used in the Red Books and Classification; on the right are the expanded terms.

5. Structure and formatting 2
Term--Subdivision --Subdivision
Double dashes (or a long dash) separate main terms from subdivisions. In MARC these are replaced with subfield codes. Terms and subdivisions always start with capital letters.
The following slides follow the layout of the Red Books which is also followed in Classification Web.

6. USE Fish USE Fishes The best way to start is to just try something…
E.g. Fish.

7. Preferred term
Fishes (May Subd Geog) UF Fish Pisces BT Aquatic animals Vertebrates RT Fisheries Fishing Ichthyology SA names of orders, families, etc. of fishes, e.g. Perciformes; Salmonidae; Tarpon NT Agnatha Air-breathing fishes

8. NT and BT
Aquatic animals (May Subd Geog) UF Aquatic fauna Water animals BT Animals Aquatic organisms NT Aquarium animals Aquatic invertebrates Fishes

9. RT
Fisheries (May Subd Geog) UF Coastal fisheries Commercial fisheries Farms, fish BT Aquaculture Wildlife utilization RT Fishery sciences Fishes NT Anchovy fisheries Arctic grayling fisheries

10. Specificity
Cats
Library cats
Longhair cats
Maine coon cat
Persian cat
Himalayan cat
Turkish Angora cat
Turkish Van cat
Foldex cats = Cats Longhair cats = Longhair cats Persian cats = Persian cat Himalayan cats = Himalayan cat Chinchilla longhair = Persian cat
Use the most specific term available.
In cases where there is a broad topic with strong coverage a particular subtopic, then a heading for both is an allowed exception, e.g. a book on cats with a particular focus on Persian cats:
Cats
Persian cat
[N.B. The chinchilla longhair is a breed of Persian with five generations of chinchilla, as recognised by the South African cat breeding organisation. Apparently.
Foldex Cat also known as the Exotic Fold a type of cat developed in the Canadian province of Quebec]

11. LC Names as LCSH
Shakespeare, William, Chaucer, Geoffrey, Meehan, Thomas. England London (England) Camden (London, England) Walmer Road (London, England)
You cannot make up LCSH terms! (Unless you are a SACO contributor) But you can use authorised LC Names, as terms as well as names formulated in according to LCSH. Confusingly, some of them turn up in LCSH, but there is normally a good reason!
Shakespeare, William, Used as a pattern heading (more later). You won’t, however find Chaucer, even though he is valid.

12. How many headings? Which topics: How many headings per topic/subtopic:
For topics comprising at least 20% of the work
Subtopics:
Generally, up to three subtopics can be treated separately.
Otherwise, use the broader topic that covers all the subtopics.
Sometimes, for very broad headings and very narrow subtopics, it may be appropriate to enter up to four subtopics separately, but no more than four.
Use common sense and judgement and, if in doubt, use broader topics.
(See SHM H 180 sections 8 and 9 for more details and examples)
How many headings per topic/subtopic:
Use the most specific heading available.
Use a broader heading if necessary to cover a topic.
Use two or more headings to bring out aspects of a topic.
No more than 10 headings.

13. LCSH Subdivisions There are four types of subdivisions:
Topical
Chronological
Geographical
Form
In general, they are added in the above order, separated by double dashes.

14. Topical subdivisions
--Social aspects (May Subd Geog) Use as a topical subdivision under topical headings for works on the effect of the item, activity, discipline, etc., and society on each other. NT –Emigration and immigration—Social aspects --Social life and customs Use as a topical subdivision under names of countries, cities, etc., and under classes of persons and ethnic groups. UF –Customs NT –Colonies—Social life and customs

15. Chronological subdivisions
--20th century Use as a chronological subdivision under headings for art and art forms of all nations, regions, and ethnic groups. Also use under individual languages and groups of languages, groups of literary authors, individual literatures, including drama, and forms and types of musical compositions. —History—20th century Use as a topical subdivision under names of countries, cities, etc., and individual corporate bodies, and under classes of persons, ethnic groups, military services, Christian denominations, and topical headings. Great Britain—History—20th century Great Britain—History—Anne, NT Scotland—History—Union, 1707
Chronological subdivisions are mostly dependent on other topical subdivisions and can only be added directly to art headings and certain other specific headings.
Chronological headings are often established in great detail for the History or Civilization of a place

16. Form subdivisions --Congresses
Use as a form subdivision under subjects for the proceedings or reports of proceedings of conferences or congresses on those subjects.
UF –Conference proceedings
--Congresses—Abstracts
--Congresses, conferences, etc. [Former subdivision]
--Meeting proceedings
--Proceedings of conferences
--Seminar proceedings
--Symposia proceedings
--Symposium proceedings
--Workshop proceedings
Use as a topical subdivision under subjects for works about conferences or congresses on those subjects.
UF –Conferences
--Meetings
--Symposia
--Symposiums
Form subdivisions are normally reasonably straightforward, but many of them can also be topical headings, which affects how they are coded.
Form subdivisions always go at the end.

17. Geographic subdivisions: when they can be used 1
Art (May Subd Geog) Art, Modern (Not Subd Geog) Paper stretching (Art)
Yes No
Geographic subdivisions are the most complicated:
You can only use them when a heading or subdivision explicitly says (May Subd Geog)
Put them as near to the end of the string as possible: after the last topical subdivision if possible.

18. Geographic subdivisions: where they can be used 2
For a book on teaching about modern art in Scotland, given the following…
Art, Modern   (Not Subd Geog) 
--Study and teaching   (May Subd Geog)
--Scotland
Art, Modern—Scotland—Study and teaching is wrong.
Art, Modern—Study and teaching—Scotland is correct.

19. Geographic subdivisions: where they can be used 3
For a book on teaching about art in Scotland, given the following…
Art teachers   (May Subd Geog)
--Social conditions
--Scotland
Art teachers—Scotland—Social conditions is correct.
Art teachers—Social conditions—Scotland is wrong.

20. Geographic subdivisions: form
Generally, geographic subdivision follows the authorised heading but is entered in reverse as Country followed by City.
England London (England) Camden (London, England) Walmer Road (London, England) River Thames (England) Rhine River
--England --England--London --England—London --England—River Thames --Rhine River
Generally, geographic subdivision is entered as Country followed by City. You cannot go lower than city level or use more than two levels. Add a separate main heading for a district if necessary.
Country in LC Names and LCSH is for the US and UK divided into states/provinces rather than US and UK (also Canada, Australia, and Malaysia: check LC when in doubt). Abbreviated often in direct order and in full as subdivisions. E.g. Toronto (Ont.) becomes –Ontario—Toronto.
Geographical features within countries are treated the same. Those across borders etc can be entered directly. The 781 of the MARC authority record is really helpful for this.

21. Geographic subdivisions: example
For a book on the social conditions of art teachers in Leith, given the following…
Art teachers   (May Subd Geog)
--Social conditions
--Leith (Edinburgh, Scotland)
…the following headings would be appropriate:
Art teachers—Scotland—Edinburgh—Social conditions
Leith (Edinburgh, Scotland)

22. Where to find subdivisions
Subject Headings Manual (SHM)
On Cataloger’s Desktop. There are lists of types of heading and the subdivisions you can use, as well as detailed guidance on the subdivisions themselves.
Pattern headings
E.g. Shakespeare, William, for literary authors.
Any subdivision used under pattern headings can be used under other headings of the same type. Lists of pattern headings are available on The SHM, including:
For individual educational institutions, follow the pattern of Harvard University.
For types of educational institutions, follow the pattern for Universities and colleges.
Classification Web
Free-floating subdivisions can be searched and browsed just like main headings, and with scope notes, etc. Also of course the main headings for the patterns can be consulted on Classification Web.

23. How many headings? Which topics: How many headings per topic/subtopic:
For topics comprising at least 20% of the work
Subtopics:
If there are up to three subtopics, treat each separately.
If there are more than four subtopics, treat each separately.
Otherwise, treat each subtopic under the broader topic.
How many headings per topic/subtopic:
Use the most specific heading available.
Use a broader heading if necessary to cover a topic.
Use two or more headings to bring out aspects of a topic.
No more than 10 headings.
2. E.g. for a book about Siamese cats, use Cats as there is no heading for Siamese cats. However, for a book about longhair cats, use Longhair cats or even Persian cats, and so on.

24. LCSH in MARC21: main headings
Topical headings: 650 Geographic headings: 651 Name headings: 600, 610, 611, 630 Not sure? Check
650 _0 $a Fishes. 651 _0 $a London (England) $a University College, London. Narnia (Imaginary place) Potter, Harry (Fictitious character)
650, 651
600, 610, 611, 630 as you would for any valid name heading
SECOND INDICATOR is ALWAYS ZERO (0) for LCSH.
Always starts with subfield $a
Always has second indicator 0 for LCSH (2 means MeSH, and so on)
The first indicator would be what you would use in a 7xx field.
Sometimes tricky to tell with some headings, e.g. Narnia, so check the MARC coding of the authority record.

25. LCSH in MARC21: main headings
Topical headings: 650 Geographic headings: 651 Name headings: 600, 610, 611, 630 Not sure? Check
650 _0 $a Fishes. 651 _0 $a London (England) $a University College, London. 650 _0 $a Narnia (Imaginary place) $a Potter, Harry $c (Fictitious character)
650, 651
600, 610, 611, 630 as you would for any valid name heading
Always starts with subfield $a
Always has second indicator 0 for LCSH (2 means MeSH, and so on)
The first indicator would be what you would use in a 7xx field.
Sometimes tricky to tell with some headings, e.g. Narnia, so check the MARC coding of the authority record.

26. LCSH in MARC21: subdivisions
Topical subdivisions: $x Chronological subdivisions: $y Geographic subdivisions: $z Form subdivisions: $v
650 _0 $a Art teachers $x Social conditions. 651 _0 $a Great Britain $x History $y 20th century. 650 _0 $a Fishes $z England $z Thames River. 650 _0 $a Narnia (Imaginary place) $v Congresses.
Note that double dashes are dropped in MARC21!

27. Accessing LCSH Classification Web https://classificationweb.net/
Password protected: UCL has subscription.
LCSH and LC Names clearly separated.
Arguably clear display and navigation.
Clear when you (May Subd Geog)
Can search free-floating subdivisions separately.
Library of Congress Authorities
Freely available.
LC Names included in subject searches.
Arguably unclear display and navigation.
Not clear when you (May Subd Geog)
MARC display available
LC Linked Data Service
Can’t search free-floating subdivisions separately
No MARC display

28. Finding out more
Broughton, Vanda. Essential Library of Congress Subject Headings. London : Facet, Chan, Lois Mai. Library of Congress Subject Headings : principles and application. 3rd edition. Englewood, Colorado : Libraries Unlimited, Library of Congress. Subject Headings Manual (SHM).