A live action role-playing game (LARP) is a form of role-playing game where the participants physically portray their characters. The players pursue goals within a fictional setting represented by real-world environments while interacting with each other in character. The outcome of player actions may be mediated by game rules or determined by consensus among players. Event arrangers called gamemasters decide the setting and rules to be used and facilitate play.

The first LARPs were run in the late 1970s, inspired by tabletop role-playing games and genre fiction. The activity spread internationally during the 1980s and has diversified into a wide variety of styles. Play may be very game-like or may be more concerned with dramatic or artistic expression. Events can also be designed to achieve educational or political goals. The fictional genres used vary greatly, from realistic modern or historical settings to fantastic or futuristic eras. Production values are sometimes minimal, but can involve elaborate venues and costumes. LARPs range in size from small private events lasting a few hours, to large public events with thousands of players lasting for days.