The Academy of St Martin in the Fields (ASMF) is an English chamber orchestra, based in London.
Sir Neville Marriner founded the ensemble as The Academy of St.-Martin-in-the-Fields in London as a small, conductorless string group. The original group numbered 11, all male. The ensemble's name comes from Trafalgar Square's St Martin-in-the-Fields church, where the orchestra gave its first concert on November 13, 1959. In 1988, the ASMF dropped the hyphens from its full name. Marriner holds the title of Life President with the ASMF.
The initial performances as a string orchestra at St Martin-in-the-Fields' church 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 ensemble from the leader's desk. On recordings, besides Marriner, Iona Brown and Kenneth Sillito have led the ASMF among others. Since 2000, Murray Perahia has held the title of principal guest conductor of the ASMF, and has made commercial recordings with the ensemble as pianist and conductor.