Find the referee at the center of the court, dressed in black and white stripes. A referee’s duties include signaling when a rally begins and ends. The referee is also responsible for officially recognizing team requests, substitutions, time-outs and communicating with the coaches at the appropriate times. Multiple referees may oversee a match.
Before play begins, the scorekeeper records team and player information. Once the game begins, scorekeepers not only track points, but also player substitutions, sanctions and time-outs. The scorekeeper keeps an eye on the individual serving the ball to track the rotation and notify referees of potential lapses. At the close of the game, the scorekeeper records the final score of the game.
The assistant scorekeeper or libero tracker is responsible for updating the scoreboard and keeping an eye on the libero. The libero tracking duty was added in 1999. This individual records changes in the libero rotation, notifying referees when problems occur in the rotation.
There are usually two line judges, one at either end of the court and in opposite corners. Line judges work with the referees, signaling to assist in making judgment calls. These officials often use flags to signal when a ball is in or out, hits the antennae of the net, or when the server commits a foot fault, or steps outside the line, as they serve.
Timer and Umpire
The umpire assists the referee in his duties throughout the game, particularly when it comes to play around the net and center line. He stands opposite the referee, outside the sideline boundary and back from the standard. The timer sits with the scorer and ensures the clock is working properly. He takes direction from the referees as to when to start and stop play. The timer times pre-match warmups as well as the three-minute intermissions between games. The timer is also expected to give an audio signal when the improper player has served or another rule infraction occurs.