The Academy of St Martin in the Fields is an English chamber orchestra, based in London.
John Churchill, then Master of Music at the London church of St Martin-in-the-Fields, and Neville Marriner (later Sir Neville) founded the orchestra as "The Academy of St.-Martin-in-the-Fields", a small, conductorless string group. The original group numbered 11, all male. The orchestra gave its first concert on November 13, 1959, in the church it was named after. In 1988, the orchestra dropped the hyphens from its full name. Marriner held the title of Life President until his death in 2016.
The initial performances as a string orchestra at St Martin-in-the-Fields played a key role in the revival of baroque performances in England. The orchestra has since expanded to include winds. It remains flexible in size, changing its make-up to suit its repertoire, which ranges from the Baroque to contemporary works.
Neville Marriner continued to perform obbligatos and concertino solos with the orchestra until 1969, and led the orchestra on recordings until the autumn of 1970, when he switched to conducting from the podium from directing the orchestra from the leader's desk. On recordings, besides Marriner, Iona Brown and Kenneth Sillito have led the orchestra, among others. Since 2000, Murray Perahia has held the title of principal guest conductor of the orchestra, and has made commercial recordings with the orchestra as pianist and conductor.