LCSH Subject Headings

The Library of Congress Subject Headings (LCSH) consist of subject headings, maintained by the United States Library of Congress, for use in bibliographic records. LC Subject Headings are an integral part of bibliographic control, which is the function by which libraries collect, organize and disseminate documents. LCSHs are applied to every item within a library’s collection, and facilitate a user’s access to items in the catalogue that pertain to similar subject matter. If users could only locate items by ‘title’ or other descriptive fields, such as ‘author’ or ‘publisher’, they would have to expend an enormous amount of time searching for items of related subject matter, and undoubtedly misslocating many items because of the ineffective and inefficient search capability.

The Subject Headings are published in five large volumes. They may also be searched online in the Library of Congress Classification Web, a subscription service. The Library of Congress issues weekly updates. Once a library user has found the right subject heading they are an excellent resource for finding relevant material in your library catalogue. Increasingly the use of hyperlinked, web-based Online Public Access Catalogues, or OPACs, allow users to hyperlink to a list of similar items displayed by LCSH once one item of interest is located. However, because LCSH are not necessarily expressed in natural language, many users may chose to search OPACs by keywords. Moreover, users unfamiliar with OPAC searching and LCSH, may incorrectly assume their library has no items on their desired topic, if they chose to search by ‘subject’ field, and the terms they entered do not strictly conform to a LCSH. For example ‘body temperature regulation’ is used in place of ‘thermoregulation’. Thus the easiest way to find and use LCSH is to start with a ‘keyword’ search and then look at the Subject Headings of a relevant item to locate other related material.