In organized sports, match fixing occurs as a match is played to a completely or partially pre-determined result, violating the rules of the game and often the law. The most common reason is to obtain a payoff from gamblers, but players may also intentionally perform poorly to gain a future advantage, such as a better draft pick or an easier opponent in a play-off. A player might also play poorly to rig a handicap system.

Match fixing, when motivated by gambling, requires contacts (and normally money transfers) between gamblers, players, team officials, and/or referees. These contacts and transfers can sometimes be found, and lead to prosecution by the law or the sports league(s). In contrast, losing for future advantage is internal to the team and very hard to prove. Often, substitutions made by the coach designed to deliberately increase the team's chances of losing (such as having key players sit out, using minimal or phantom injuries as an excuse), rather than ordering the players actually on the field to intentionally underperform, are cited as the main factor in cases where this has been alleged.

Match fixing generally refers to fixing the final result of the game. Another form of match fixing, known as spot fixing, involves fixing small events within a match which can be gambled upon, but which are unlikely to prove decisive in determining the final result of the game.

Other names for match fixing include game fixing, race fixing, sports fixing, or hippodroming. Games that are deliberately lost are sometimes called thrown games. When a team intentionally loses a game, or does not score as high as it can, to obtain a perceived future competitive advantage, the team is often said to have tanked the game instead of having thrown it. In pool hustling, tanking is known as dumping. In sports where a handicap system exists and is capable of being abused, tanking is known as sandbagging.