Justine Henin (born 1 June 1982), formerly known as Justine Henin-Hardenne (2002–2007), is a professional Belgian tennis player and former World No. 1.
Henin has won 43 WTA singles titles and seven Grand Slam singles titles, including four French Open titles, one Australian Open title, and two US Open titles. She has also won the year-ending Sony Ericsson Championships twice and the singles gold medal at the 2004 Summer Olympics.
Tennis experts cite her mental toughness, the completeness and variety of her game, her footspeed and footwork, and her one-handed backhand (which John McEnroe has described as the best single-handed backhand in the women's or men's game) as the principal reasons for her success.