Billie Jean King once that if you want to be the best, you must never let anyone, anyone, know what you really feel. You see, she told me, they can't hurt you if they don't know. Concerning the qualities of a champion tennis player, King said, King's friend Elton John wrote the song “Philadelphia Freedom”, a nod to her World TeamTennis team, for King. Released New Year's Day 1975, became a number 1 hit. Charles M. Schulz, creator of the "Peanuts" comic strip, was an admirer and close friend. Schulz referred to King several times in "Peanuts" and used the comic strip to
Billie Jean King of America, which opened in 2008. The museum is the home of the Billie Jean King International Women's Sports Center, a comprehensive women's sports hall of fame and exhibit. King and her then-husband Larry co-founded World Team Tennis in 1974. The couple used their savings to put on a team tennis event at the Oakland Coliseum. King remained involved with World Team Tennis for decades, eventually sharing ownership with her ex-husband, her life partner Ilana Kloss and USTA. In 1999, King was elected to serve on the Board of Directors of Philip Morris Incorporated, garnering some criticism from anti-tobacco groups.