William Speed Lane Fox-Pitt is an English equestrian who competes in eventing. His career highlights include winning three Olympic medals in the team event, with silver in 2004 and 2012, and bronze in 2008. At the World Equestrian Games, he won team gold and individual silver in 2010, and team silver and individual bronze in 2014. He also won World team medals in 2002 and 2006. At the European Championships, he has won six team gold medals, as well as Individual silver in 1997 and 2005, and Individual bronze in 2013. He is the recordman CCI*****'s winner with 14 grand slam titles. In 2011, he became the first rider to win five different five-star events, having won the Burghley Horse Trials a record six times, Rolex Kentucky three times, Stars of Pau twice, the Badminton Horse Trials twice, and the Luhmühlen Horse Trials once (2008). A serious fall in 2015 left him in a coma for two weeks, but he came back to make the British eventing team and attend the 2016 Summer Olympics. He was appointed Member of the Order of the British Empire (MBE) in the 2018 Birthday Honours.

Eventing is an equestrian event where a single horse and rider combine and compete against other competitors across the three disciplines of dressage, cross-country, and show jumping. This event has its roots in a comprehensive cavalry test that required mastery of several types of riding. The competition may be run as a one-day event (ODE), where all three events are completed in one day or a three-day event (3DE), which is more commonly now run over four days, with dressage on the first two days, followed by cross-country the next day and then show jumping in reverse order on the final day. Eventing was previously known as Combined Training, and the name persists in many smaller organizations. The term "Combined Training" is sometimes confused with the term "Combined Test", which refers to a combination of just two of the phases, most commonly dressage and show jumping.