Music is one of the richest and most complex subjects, with a very large literature. It embraces a great variety of traditions and genres, and the vocabulary required for music indexing is very considerable. There are no widely used specialist controlled vocabularies for music, and, apart from its use in general libraries, LCSH is probably the most substantial subject cataloguing tool available to music librarians.

Like those for the visual arts and media, music headings have close similarities to the headings for literature, and several of the sections below will parallel the literature chapter, although music is unusual in having a tripartite structure of books about music, works of music (scores and parts in printed music) and recordings. Music has some additional features; these include the need to represent musical forces – musical instruments, voices and ensembles – and their combination in headings for sheet music. These can become complex, apart from the representation of specific compositions, and there is also a substantial number of headings for material on individual instruments. Finally, the way in which named compositions are handled is more complicated than that for literary works.

Numbers of main headings exist for music theory, performance and criticism, such as Arpeggios, Chords (Music), Counterpoint, Harmony, Relative pitch, Sight-reading, Tonality and so on. These present no more difficulty than the headings for any other subject, and will not be discussed here.

The distinctions between books about music, scores and recordings are not very clearly signposted within the heading itself, but some free-floating subdivisions can be used, and certain conventions are employed in the formation of headings for books and scores that indicate the difference to those in the know. Just as music libraries usually separate books about music and scores, and arrange them in different ways, so LCSH has different approaches to the headings for books and scores.

General works about music: period and place

A few years ago the headings for music in particular places and times were rationalized, so these are rather different in form from other arts subjects. Inverted headings are not used to represent the idea of nationality in music, and there are no headings of type ‘Music, French’ (or ‘French music’). Instead, geographic subdivisions and period free-floating subdivisions are used to express music by place and time.