After a time working in the shipyards, Lamont moved to London to play with Kenny Graham's Afro Cubists and (switching to tenor saxophone) with the Johnny Keating band in 1957.
[2] For several decades Lamont worked as a freelance musician (on flute and clarinet as well as saxophone), based around Archer Street in Soho and playing in the surrounding jazz clubs.
He often performed with British bands accompanying American vocalists, including Fred Astaire, Tony Bennett, Bing Crosby, Sammy Davis Jr., Marlene Dietrich, Peggy Lee and (for 19 seasons) with Frank Sinatra.
[7] He became part of the library music recording group WASP, along with Steve Gray on piano, Brian Bennett on drums, Dave Richmond on bass and Clive Hicks on guitar.
Blossom Dearie, Natalie Cole, Cleo Laine and Norma Winstone were among those who recorded his songs.
[10] In May 2019 just over four weeks before he died, Lamont returned to the town of his birth, Greenock, to perform a homecoming gig with singers Esther Bennett and Daniela Clynes.