Patrick made an impact on hockey in various capacities, starting as one of the top defensemen at the turn of the 20th century.

The "Silver Fox" began his career with Brandon of the Manitoba & Northwestern Hockey Association in 1903 but played most of his career with Victoria of the Pacific Coast Hockey Association (1911-16 and 1918-22).

Patrick played one career regular-season NHL game with the New York Rangers on March 20, 1927. A Stanley Cup Playoffs appearance the next season proved more memorable. In Game 2 of the 1928 Stanley Cup Final against the Montreal Maroons, Patrick, then 44 years old and general manager and coach of the Rangers, put himself into the game at goalie after starter Lorne Chabot sustained an eye injury during the second period. Lester made 17 saves on 18 shots in a 2-1 win for New York, which went on to win the first Cup in its history.

Patrick also coached the Rangers to the Cup in 1933. He was New York's general manager from 1940, when the Rangers again won the Cup, to 1946.

Patrick and his brother, Frank, financed the first artificial ice arenas in British Columbia to house games for the PCHA, which they formed in 1911. They had an impact on modern hockey in other ways, introducing innovations to the game including numbered jerseys, player changes "on the fly," penalty shots and the blue line.

Patrick was elected to the Hockey Hall of Fame in 1947. He died on June 1, 1960. Named in his honor, the Lester Patrick Trophy has been awarded annually by the NHL and USA Hockey for outstanding service to hockey in the United States since 1966.

Patrick's sons, Lynn and Frederick Murray "Muzz" Patrick would have their own NHL careers. Muzz Patrick played five seasons for the Rangers before coaching them for four seasons (1953-55, 1959-60 and 1962-63). Lynn Patrick, who like his father would be inducted into the Hockey Hall of Fame (1980) played 10 seasons with the Rangers and was the first GM of the St. Louis Blues in 1967.

Lester Patrick is also the grandfather of Craig Patrick, who was GM of the Rangers and Pittsburgh Penguins and inducted into the Hockey Hall of Fame in 2001, and Dick Patrick, president of the Washington Capitals.