Daniel Jaffé is an author and biographer specialising in 20th-century music, whose interest in Gustav Holst’s music has been something of a lifelong passion – he is presently researching the composer’s life and work for a full-length biography. A regular contributor to BBC Music Magazine, he is also a recognised specialist in Russian music and has published a biography of Sergey Prokofiev (Phaidon) and a Historical Dictionary of Russian Music, as well as contributing extensively to the just published Cambridge Stravinsky Encyclopedia.