Justine Henin (French pronunciation: [ʒystin ɛnɛ̃]; born 1 June 1982) is a Belgian former professional tennis player. She was ranked as the world No. 1 in women's singles by the Women's Tennis Association (WTA) for 117 weeks, including as the year-end No. 1 in 2003, 2006 and 2007. Henin won 43 WTA Tour-level singles titles, including seven majors (four at the French Open, two at the US Open and one at the Australian Open), as well as an Olympic gold medal at the 2004 Athens Games and two Tour Finals titles. Coming from a country with little success in the sport, Henin (alongside Kim Clijsters) helped establish Belgium as a leading force in women's tennis, leading the country to its first Fed Cup crown in 2001. As of 2026, she is still the most recent female player to have reached the finals of all four grand slam tournaments within the same calendar year. Henin was known for her all-court style of play and for being one of the few female players to use a single-handed backhand. Tennis experts cite her mental toughness, the completeness and variety of her game, her footspeed and footwork, and her one-handed backhand (which all-time great John McEnroe described as "the best single-handed backhand in both the women's or men's game") as the principal reasons for her success. She retired from professional tennis on 26 January 2011, due to a chronic elbow injury. In June 2011, she was named one of the "30 Legends of Women's Tennis: Past, Present and Future" by Time. In 2016, she became the first Belgian tennis player inducted into the International Tennis Hall of Fame and in 2023, the International Tennis Federation awarded Henin its highest honor, the Philippe Chatrier Award.