Sir Henry Richard Amherst Cecil (11 January 1943 – 11 June 2013) was a British flat racing horse trainer. Cecil was very successful, becoming Champion Trainer ten times and training 25 domestic Classic winners. These comprised four winners of the Derby, eight winners of the Oaks, six winners of the 1,000 Guineas, three of the 2,000 Guineas and four winners of the St Leger Stakes. His 1000 Guineas and Oaks successes made him particularly renowned for his success with fillies. He was noted for his mastery at Royal Ascot, where he trained 75 winners.