Sally Jane Janet Gunnell is a British former track-and-field athlete, active between 1984 and 1997, who won the 1992 Olympic gold medal in the 400 metres hurdles. During a golden 24-month period between 1992 and 1994, Gunnell won every international event open to her, claiming Olympic Games, World Championship, European Championship, Commonwealth Games, Goodwill Games, IAAF World Cup and European Cup golds in the event, and breaking the British, European and World records in it. She is the only female British athlete to have won all four 'majors'; Olympic, World, European and Commonwealth titles, and was the first female 400 metres hurdler in history to win the Olympic and World titles and break the world record. Her former world record time of 52.74 secs in 1993, still ranks in the world all-time top ten and is the current British record. She was named World and European Female Athlete of the Year in 1993, and was made an MBE in 1993 and an OBE in 1998.

The 400 metres hurdles is a track and field hurdling event. The event has been on the Olympic athletics programme since 1900 for men and since 1984 for women.