John Arthur Lanchbery OBE (15 May 1923 – 27 February 2003) was an English-Australian composer and conductor, famous for his ballet arrangements. He served as the Principal Conductor of the Royal Ballet from 1959 to 1972, Principal Conductor of the Australian Ballet from 1972 to 1977, and Musical Director of the American Ballet Theatre from 1978 to 1980. He continued to conduct regularly for the Royal Ballet until 2001.

Lanchbery was widely considered (including by Nureyev) to be the greatest ballet conductor of his time, and to be ‘a conductor and music director of unmatched experience’ who was ‘directly responsible for raising the status and the standards of musical performance'. Maina Gielgud, Artistic Director of Australian Ballet, stated that "He [Lanchbery] is not only the finest conductor for dance of his generation and probably well beyond". One critic wrote that ‘the music was always on its best behaviour’ when Lanchbery was conducting. He was also famous for his re-adaptation of canonical works.