Des Smith grew up in the Ottawa area and played his junior hockey for the Montagnards. He played from 1930 to 1935 before moving across the pond to play in Britain for two seasons. Smith then made his NHL debut in the 1937-38 season with the Montreal Maroons.
He was traded to the Maroons' cross-town rivals, the Canadiens, but spent the majority of the 1938-39 season with the AHL's New Haven Eagles. The next season saw him dealt yet again, this time to the Blackhawks, who turned around and sent him to the Boston Bruins just 24 games later.
It was in Boston that Smith enjoyed his most success. A talented Bruins team that had such players as Bobby Bauer, Milt Schmidt, and Roy Conacher joined Smith in a sweep of the Red Wings to take the Stanley Cup in 1941. He played one more season before retiring from the NHL.
Smith moved back to Ottawa in 1942 where he coached the Army team for two seasons and then strapped the skates back on to play for two more seasons before retiring as a player once again in 1946. Smith laced up the skates yet again, this time to be a referee, in the AHL for several seasons. After hockey, he rekindled a fondness he had had for the racetrack. He became the announcer at the Carleton Raceway in Ottawa in 1962 and served as the public relations director until his untimely passing in 1981 at the age of 67.