Volleyball at the Olympics consists of two tournaments: one for the men, and one for the women. Each tournament is made up of 12 teams, which qualified for the Games by placing high enough in a previous tournament that served as an Olympic qualifier.
The Tokyo Olympic volleyball tournament begins on July 24, Day 1 of the Games, and concludes on Aug. 8, Day 16 and the final day of the Games.
An Olympic volleyball team consists of 12 players. One of the players, other than the libero, is the team captain. Six of a team's players are on court at once, and they rotate positions clockwise every time their team wins back the serve. The three players at the net are the only ones who can jump and spike or block near the net. The backcourt players must hit the ball over the net while standing or jumping from behind the attack line, which separates the front and back portions of the court.
Volleyball has become very specialized. Most teams will start a match with a setter, two middle blockers, two outside hitters and a universal spiker. Only select players will take part in service reception. Players also have specialist positions for attack and defense. Substitutions are allowed during the game.
The team captain serves as the game captain while on the court. When not on the court, another player that is not the libero assumes this role. When the ball is out of play, only the game captain may speak to the referees about the application or interpretation of rules, call timeouts, request substitutions, etc. The team captain must have a stripe underlining his or her jersey number on the chest.
After the 1996 Olympics, the FIVB introduced the libero. This player is a defensive specialist designated by a team and wears a different colored jersey than the rest of the team. He or she can be substituted in the backcourt on an unlimited basis, without needing the referee's approval. Meaning "free" in Italian, the libero is not allowed to serve, spike the ball over the net, or rotate into one of the front-row positions. There must be at least one point played between a libero substituting off for a player and going back on the court for another player.
In the case of injury to the libero, the team coach, with the permission of the first referee, can appoint another player as libero for the rest of the game. However, the original libero cannot return to play again in the same match. The libero adds an extra dimension to defense in the backcourt, improves serve reception, helps extend rallies, and provides a vital role to shorter players.
Two referees supervise an Olympic volleyball match, in cooperation with a scorer and line supervisors. The first referee oversees the match from a perch above the net and has exclusive authority to issue warnings, sanction misconduct, call faults committed by the server or net players, settle disputes, etc.
The second referee, standing outside the court near the post opposite the first referee, is responsible for monitoring the use of timeouts and substitutions, calling violations committed on the court – i.e., penetration into the opponent's court – and controlling the work of the scorer.
Sitting at a table opposite the first referee, the scorer is exclusively responsible for registering lineups, recording the number and name of the libero, tracking points scored, noting timeouts and player substitutions on the scorecard, etc.
The line judges, placed in the free zone at each corner of the court, use flags to indicate whether a ball landing near a line is in or out. They also call foot faults on the server.