A 2008 USATT Hall of Fame member, Sean O’Neill has represented the United States in every international competition possible, including the Pan Am Games, Olympic Games, World Championships, World Cup (team, doubles, and singles), and various international championships.

A five-time U.S. Men’s Singles, Doubles Champion, and six-time U.S. Mixed Doubles Champion, Sean won a total of twenty-eight U.S. Olympic Sports Festival medals, of which twenty-one were gold. A member of four Pan Am Games teams, Sean won two Gold, five Silver, and one Bronze medals.

As a Coach, O'Neill led the 2003 and 2007 US Para Pan Am Teams in addition to the 2004, 2008, and 2012 US Paralympic Teams.

Sean worked for NBC Universal at the Olympic Games in 1988, 2004, 2008, and 2012 as a color analyst for table tennis. 

Sean currently resides in Portland, Oregon.