"The Beethoven Thesaurus is a list of approximately 9,000 subject and category (formerly known as genre) terms. The thesaurus groups these terms together in nine sections (or hierarchies). Terms are listed in alphabetical order within each section, with instructions on the scope of the terms, their relationships with other terms in the Thesaurus, and unused synonyms. Each listing might also include instructions to the indexer on how to apply the term to a particular subject area. In order to facilitate use by the largest audience possible, the Thesaurus terms were derived from Library of Congress Subject Headings (LCSH) and subdivisions whenever possible. Additional headings more specific to Beethoven studies were created when necessary to lead users to subjects that they cannot search with LCSHs. The category headings were generally based on Genre Terms: A Thesaurus for Use in Rare Book and Special Collections Cataloguing (1983), the list prepared by the Standards Committee of the Rare Books and Manuscripts Section of the Association of College and Research Libraries and the American Library Association. As needed, these Category terms were supplemented with music and Beethoven-related terms. Used for searching the Beethoven Gateway."