At the age of sixteen John entered the Royal College of Music. He studied composition with Gordon Jacob, oboe with Leon Goossens, and clarinet with Frederick Thurston. This education ended in 1939 with service in World War II, at the end of which, he returned to London to teach composition at the Royal College of Music.
Addison is best known for his film scores. He won an Academy Award and a Grammy Award in the Best Original Score from a Motion Picture or Television Show category for the music to the 1963 film, "Tom Jones". He also won a BAFTA Award for "A Bridge Too Far" (1977). His other film scores included "A Taste of Honey" (1961), "Smashing Time" (1967), "Sleuth" (1972), "Swashbuckler" (1976) and the television series "Centennial" (1978).
He composed the theme music for the television series "Murder, she wrote", for which he won an Emmy. Addison will also be remembered as the composer Alfred Hitchcock turned to when the director ended his long relationship with Bernard Herrmann over the score to his 1966 film "Torn Curtain".
He had a personal connection to "Reach for the Sky" (1956) which he scored, since Douglas Bader (the subject of the movie) was his brother-in-law.
For the theatre, Addison wrote the music for John Osborne's plays "The Entertainer" (1957) and "Luther" (1961). He collaborated with John Cranko on a revue, "Cranks" in 1956.
John is on the list of those who attended the 23H reunion in 1959.