David O’Connor was a member of almost every U.S. Equestrian Team from 1986 until his retirement in 2004 and is one of America’s most successful international three-day event riders. In 1995, O’Connor won both Rolex Kentucky Three-Day Event and the Fair Hill CCI3*. The following year O’Connor rode Giltedge as a member of the silver medal-winning team at the 1996 Atlanta Olympic Games and was fifth individually aboard Custom Made. In 1997, O’Connor rode Custom Made to become only the second American to win the Badminton CCI4*. O’Connor’s performances at the Olympics and Badminton led him to the title of USEA Rider of the Year in 1996 and 1997.

At the 1999 Pan American Games in Winnipeg, O’Connor and Giltedge were members of the gold medal team and were the individual silver medalists. In 2000, O’Connor rode Custom Made to win the individual gold medal at the Sydney Olympic Games. He was also a member of the bronze medal team aboard Giltedge, who then went on to win the Rolex Kentucky Three-Day Event the following year. Two years later, O’Connor once again stood on top of the podium as a member of the gold medal-winning team at the World Equestrian Games in Jerez, Spain. His partner was Giltedge, who with O'Connor represented the U.S. Team an outstanding five times.

O’Connor is now retired from international competition but continues to support the sport by training riders and horses and designing courses across the country. He was the President of the United States Equestrian Federation from 2004-2012. He served as the coach for the Canadian Eventing Team from 2006 through 2012, leading them to silver medals at the 2007 Pan American Games and the 2010 World Equestrian Games. In 2013, he was appointed the Chef d’Equipe of the United States team, a role he held until 2017. In 2018 he became the chair of the FEI Eventing Committee.