William Arthur O'Donnell (born May 4, 1948 in Springhill, Nova Scotia, Canada) is a prominent harness racing driver. O'Donnell's parents, Etta and Henry, were both heavily involved in the local racing circuit. After graduating from high school, he became second trainer for , and moved to Saratoga Springs, New York, where in 1979 he set the all-time record for most wins (269) at a single track in a single season. Later he went to the Meadowlands in New Jersey on the Grand Circuit.