The usefulness of small-scale dictionaries and encyclopaedias of music is often a moot point since many contain short journalistic entries that satisfy only the most basic research or passing interest. Although their function seems to be to provide brief background information, they can, when well produced, have a useful role in referring students and scholars to other more detailed articles and monographs that might fulfil their requirements. The Oxford Composer Companions: J. S. Bach is such a volume; edited by Malcolm Boyd, the book contains numerous short articles written by more than 40 scholars, most of who are renowned for outstanding commentaries concerning Bach and his world. They are not, however, as restrictive as might be at first imagined, since, as the companion demonstrates, numerous 'unrelated' entries allow for a wider exploration of Baroque music, its genres, composers, centres of excellence, etc., making this a handy reference tool for more than Bach students alone. Thus, although each entry is oriented towards Bach in one respect or another, ample background information is provided, therefore enabling the reader to see it in a slightly wider context. Many of Bach's principal works are described in detail, either as short entries (in the case of the cantatas and their descriptions) or as one of a series of longer articles that sporadically occurs through the volume and which examines a wide range of subjects. For example, Michael Talbot examines the origin of the concerto and its development by Bach, John Butt provides informative background notes and a description of the Goldberg Variations, and Robin Leaver's Reception and Revival looks at the impact of Bach's music during his lifetime, and its influence on later generations of musicians worldwide.

Interestingly, some of the entries are not restricted to Baroque issues alone, and several examine topics that are more contemporary. For example, a range of twentieth-century performers and composers is represented, including such renowned interpreters as harpsichordist, Wanda Landowska, or the jazz pianist Jacques Loussier and his Play Bach trio.

Although a large proportion of the contents might appear to be of little use other than as reference points and sources of bibliographical information, a thematic overview allows the reader to select appropriate entries within a more constructive framework, thus enabling readers to follow certain more fulfilling topics such as Bach's pupils, genres or matters relating to performance practice.

Thirty well-produced plates and numerous musical extracts help to illustrate texts, and three entabulated appendices provide a list of Bach's works, an index of text incipits and a chronology of Bach's life that includes not only references to his music, but also to those of other musicians and contemporary events.

With more than 900 entries, it becomes clear how wide a range any complete study of Bach and his music would be, and it is unfortunate (but understandable) that such a volume has to be so comprehensive. However, as a quick reference tool it is a valuable resource for all interested in Baroque music.

John Woodford