Harry Sinden served as the General Manager and coach for the Boston Bruins for close to 30 years. He is currently president of the Bruins.

Sinden coached the Canadian National team during the 1972 Summit Series. He also coached the USA National Women's team at the 1998 Winter Olympic Games.

Harry was the captain of the Whitby Dunlops when they won the Allan Cup in 1957. Sinden was part of that team when it won the World Hockey Championships for Canada in Oslo, Norway, in 1958.

Before 1972, Harry Sinden was the head coach of the Bruins, coaching a team loaded with stars such as Bobby Orr and Phil Esposito to the team's 1st Stanley Cup in over 30 years. After the Cup win and before he was called out of retirement to coach the Canadian team in the '72 Summit Series, Harry worked in the home construction business in Rochester, NY. After the Summit Series, he became Boston's general manager.

As a general manager,  Harry Sinden managed to put top-notch teams on the ice in Boston, but he was also the center of controversies ranging from video replays to salary arbitration, and was under frequent fire from Bruins' fans for his perceived penurious ways. During the 1996-97 season, the NHL fined him 5,000 dollars for verbal abuse towards video replay official Ian Sandercock after a goal was disallowed in the 2nd period during a game against the Ottawa Senators. Two years later, Harry became the first general manager in league history to refuse arbitration for one of his players. That player was Dmitri Khristich, a 29-goal scorer who was awarded 2.8 million dollars.

Harry Sinden was elected to the Hockey Hall of Fame in the Builders category.

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