O'Neill has managed Grantham Town, Wycombe Wanderers, Norwich City, Leicester City, Celtic, Aston Villa and Sunderland. He guided Leicester City to the Football League Cup final three times, winning twice. As Celtic manager between 2000 and 2005, he led that club to seven trophies including three Scottish Premier League titles and the 2003 UEFA Cup Final. After joining Aston Villa he achieved three consecutive sixth-place finishes in the English Premier League and guided them to the 2010 Football League Cup Final.