In sports, a starting lineup is an official list of the set of players who will participate in the event when the game begins. The players in the starting lineup are commonly referred to as starters, whereas the others are substitutes or bench players.

The starters are commonly the best players on the team at their respective positions. Consequently, there is often a bit of prestige that is associated with being a starter. This is particularly true in sports with limited substitutions, like baseball or association football (soccer).

When listing a team's lineup, it is common in some sports to include each player's uniform number and their position, along with their name. Position are often designated by abbreviations that are specific to the sport (for example, in American football; "SS" for strong safety). In both baseball and basketball, it is common for a player's position to be denoted by a number, for example: in baseball scorekeeping the shortstop position is "6", while in basketball the small forward position is known as the "three". Thus, the lineups for some sports can include a uniform number, the player's name, and an abbreviation (consisting of letters or numbers) denoting a position.