In basketball, a flop is an intentional fall or stagger by a player after little or no physical contact by an opposing player in order to draw a personal foul call by an official against the opponent). The move is sometimes called acting, as in "acting as if he was fouled"). Flopping is generally considered to be unsportsmanlike because it is inherently designed to deceive the official, but it is widely practiced and even perfected by many professional players). The player that commits the act is referred to as a flopper).

Flopping effectively is not easy to do, primarily because drawing contact can sometimes result in the opposite effect—a foul called on the defensive player—when too much contact is drawn or if the player has not positioned himself perfectly). In the NBA, the penalty for "flopping" is a non-unsportsmanlike conduct technical foul if caught in-game, and a fine if caught after the game in video reviews. In FIBA play, the penalty is a technical foul that counts as one of two towards ejection).

Under the new NBA rule, when a game official calls a flop – or a physical act that reasonably appears to be intended to cause the officials to call a foul on another player – the offending player will be charged with a non-unsportsmanlike technical foul and the opposing team will be awarded one free throw attempt, which could be attempted by any player who is in the game when the technical foul is assessed. A player will not be ejected from a game based on flopping violations. The flopping violation will run on a one-year trial for next season, with a decision on its effectiveness required next offseason.