Originally selected 18th (second round) in the 1970 NHL Entry Draft by the Philadelphia Flyers (the Flyers' first pick of the draft), Clement played four seasons with the Flyers (as well as in minor league teams at Quebec City and Richmond, VA), and was part of the Stanley Cup-winning Flyers teams of 1973–74 and 1974–75 as the 4th line Center. Prior to the 1975 NHL Amateur Draft, he was traded to the Washington Capitals for their right to draft Mel Bridgman, as the first overall draft pick that year. After playing just 46 games with the Capitals (and serving as the team captain) in the 1975–76 season, he was then traded to the Atlanta Flames for Gerry Meehan, Jean Lemieux and a Round 1 pick in the 1976 NHL Amateur Draft. He would play with the Flames organization in both Atlanta and Calgary, until his retirement following the 1981–82 NHL season. He played in two NHL All-Star Games, in 1976 and 1978. In 719 regular season games, he scored 148 goals, earned 206 assists, and 383 penalty minutes. In 50 playoff games, he collected five goals and three assists.