After two unsuccessful years in Cleveland, the Barons (formerly the California Golden Seals) merged with the Minnesota North Stars, temporarily reducing the NHL to 17 teams.
The Montreal Canadiens dominated the regular season, finishing 51 points ahead of the Detroit Red Wings in the Norris Division and 16 points ahead of the Boston Bruins, who had the league's second best record.
Montreal's Guy Lafleur was the NHL's scoring leader for the third year in a row, and he won the Hart Trophy as the league's MVP for the second straight year. Goaltenders Ken Dryden and Michel 'Bunny' Larocque again shared the Vezina Trophy, and Bob Gainey became the first winner of the Selke Trophy, awarded to the league's best defensive forward.
The New York Islanders were continuing their rise toward the top of the league, dethroning the Philadelphia Flyers in the Patrick Division. Denis Potvin won the Norris Trophy as the NHL's top defenseman and Mike Bossy won the Calder Trophy as rookie of the year.
However, Toronto upset the Islanders in a seven-game semifinal. The Canadiens then swept the Maple Leafs to reach the finals, where they came up against Boston for the second year in a row. The Bruins had swept the Chicago Black Hawks and eliminated the Flyers in five games.
Boston made it more difficult this time around, but the Canadiens still came away with their third straight Stanley Cup championship. After Montreal won two at home, the second in overtime, the Bruins also took two home victories, one of them in OT. But the Canadiens won the next two by 4-1 scores.
Montreal defenseman Larry Robinson, who shared playoff scoring honors with Lafleur, won the Conn Smythe Trophy.