tanenbaum has had a long-standing interest in the sports and entertainment area and to that end in 1991 he spearheaded the effort to bring an nba franchise to toronto. in 1996 an interest was acquired in the toronto maple leafs hockey club and arena. in 1998 tanenbaum was an active force in the acquisition of the toronto raptors basketball team and the scotiabank arena, which, with the toronto maple leafs formed maple leaf sports and entertainment. tanenbaum is chairman of mlse, chairman of the board of the national basketball association, and a governor and member of the executive committee of the national hockey league, the nba, and major league soccer (toronto fc professional soccer club, which mlse also owns). he is co-chair – toronto 2026 fifa world cup. he is a member of the board of the hockey hall of fame in toronto, ontario.