High Quality Content by WIKIPEDIA articles! The Library of Congress Subject Headings (LCSH) comprise a thesaurus (in the information technology sense, a controlled vocabulary) 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 miss locating many items because of the ineffective and inefficient search capability.