He also studied conducting with Malcolm Sargent and formed a lifelong friendship with fellow-student Gerald Finzi with whom he attended Richard Strauss's Alpine Symphony at the Royal Albert Hall.
During World War II, Ferguson helped Myra Hess run the popular, morale-boosting series of concerts at the National Gallery.
From 1948 to 1963 he taught at the Royal Academy of Music, his students there including Richard Rodney Bennett, Cornelius Cardew and Ian Kellam.
His editions of such repertoire as early keyboard music and the complete piano sonatas of Schubert are outstanding, with a meticulous attention to detail which makes them authoritative (Tait).
[4] In his later years he lived in a white-painted converted farmhouse in Barton Road in Cambridge, his quiet hospitality legendary (Tait).
In the same decade he also prepared an edition of letters between himself and Gerald Finzi, which is an invaluable source of information on the professional lives of Ferguson and his circle.
Late in his life, a friendship with the German singer Reiner Schneider-Waterberg led to his rediscovering a song written in 1958 as part of incidental music for a William Golding play, The Brass Butterfly, and subsequently rearranging it for counter-tenor and piano (originally harp) as "Love and Reason" (1958/1994), a moving postscript to a compositional output whose great characteristic is powerful emotions expressed through superb and strictly controlled craftsmanship.