Bach's cello suites are among the most extraordinary works - both joyful and profound - written for the instrument. In his new book, 'The Bach Cello Suites: A Companion', published by Faber, Steven Isserlis draws on decades of reflection on this music, sharing his views and encouraging us to listen in even greater depth. He joins Gramophone Editor Martin Cullingford to talk about his book and the music. Excerpts throughout are taken from his recording of the suites, available on the Hyperion label, Gramophone's Instrumental Award winner back in 2007. This Gramophone Podcast is produced in association with Leipzig – the City of Music.