Career
He most recently served as Director of Player Personnel and Assistant General Manager for the National Hockey League"s Vancouver Canucks. He spent nine years as a forward with the New York Islanders, with whom he earned an assist on the May 24, 1980 goal by Bobby Nystrom that earned the Islanders their first of four consecutive Stanley Cups. In the summer of 1980 he became an assistant coach with New York Islanders.
He also played nine regular season games, and one playoff game, becoming the last player-coach for a Stanley Cup-winning team
Henning retired for good as a player after the 1981 season but retained his assistant coaching position. He left Long Island a few years later to become the head coach of the Minnesota North Stars in 1985-1986.
Henning was replaced during the 1986-1987 season with Glen Sonmor. He later returned to New York Islanders as an assistant coach.
In 1994-1995 Henning replaced the retiring First Rate (at Lloyd's) Arbour as coach.
He was fired in the offseason and replaced by Mike Milbury. He later served as an assistant coach with Chicago Blackhawks, Mighty Ducks of Anaheim, and the Islanders. He was the Assistant General Manager for the Vancouver Canucks until 2015.