After working 1948-55 as a reporter for the Hamilton Spectator, the Toronto Telegram, and the Montreal Star, Lees was music and drama critic 1955-9 for the Louisville (Kentucky) Times and editor 1959-62 of the jazz magazine Down Beat (Chicago). Working on a freelance basis, he also wrote for Stereo Review (New York) and High Fidelity (Great Barrington, Massachusetts), Maclean's, the Toronto Star, the Toronto Globe and Mail, The New York Times, and other publications. He contributed liner notes to close to 100 recordings of artists including Stan Getz, John Coltrane, and Quincy Jones. In 1967 he published a novel, And Sleep Until Noon. He received the ASCAP-Deems Taylor Award in 1978 for a series of articles published in High Fidelity about US music, and won the award on two subsequent occasions. In 1981 he established his own monthly Jazzletter (Ojai, California), which became an influential source of informed opinion, by Lees and others, within the industry.