Martin Johannes Sebastian Isepp (30 September 1930 – 25 December 2011) was an Austrian‐born British pianist, harpsichordist, conductor and teacher. He had an international career, and worked with leading singers for several decades. Among those with whom he performed were Janet Baker, Hugues Cuénod, Hans Hotter and Elisabeth Schwarzkopf. For more than forty years he was associated with Glyndebourne Festival Opera, and he held posts in opera houses and music academies in Britain, continental Europe and North America.