He was a member of four Great Britain Ryder Cup teams in the late 1940s and 1950s, and won several tournaments in Europe during his career.

[3] In late 1934 he went back to Sheffield and began working at Dore and Totley, replacing Harry Dean.

Also in 1947, Lees won the Dunlop Masters tournament,[11] and finished the Open Championship in a tie for sixth place,[13] having held a share of the lead entering the final round.

This time, he won his first match, in foursomes, as he and Dick Burton defeated Lloyd Mangrum and Sam Snead by a 1-up margin.

[17] For the season, Lees was the second-place finisher in the British golf circuit's order of merit standings.

At the 1951 Ryder Cup, he started off in foursomes, teamed with Charlie Ward and the pair posted a 2&1 victory against the American duo of Oliver and Henry Ransom.

[19] At the 1954 Dubtex Tournament in Ireland, Lees shot a 66 in the third round to set a Portmarnock Golf Club scoring record, en route to tying for first place in the event with Christy Greene.

[11] The Times later wrote of his Cup performances, "It was an era when the United States made a habit of overpowering any British team, but Lees emerged with his head high.

[21] During a qualifier in Stoneham for the News of the World Match Play tournament—which doubled as Britain's southern championship—he shot another 65 to break a record, and won the event.

In what the Associated Press called "the first twilight championship match on record," Lees lost to Goggin by a 5&3 score.

Lees improved the situation by attracting new members; The Times later wrote that he took on the role of "self-appointed recruiting agent.

[28] Harold was less successful than his brothers as a tournament golfer but he did qualify for the 1956 Open Championship, missing the cut by 3 shots.