Williams is a silver medalist in the 100 meters at the 2004 Summer Olympics and a 4-time medalist at the World Championships in Athletics, where she won (together with Angela Daigle, Muna Lee and Me'Lisa Barber) a gold medal in the 4x100 m relay in 2005 and 2007, as well as gold and silver in the 100m in 2005 and 2007 editions of the meet.