BEIJING, Sept. 3 -- The goal of the game is for teams to send the ball over the net through the crossing space and to ground it on the court of the opposing team. Each team is allowed to have up to three contacts with the ball, before it returns it towards the opposing team. The block is not considered as a contact.

    Each game consists of a maximum of five sets. Each of the first four sets is completed when a team wins 25 points, with a minimum lead of at least two points over the opposing team. In case of a tie at 24-24, the set continues until one of the teams gets a lead of two points and is declared winner of the set. In the case of a 2-2 set draw, a fifth set follows which is completed when a team wins 15 points, again with a difference of at least two points over the opposing team. The winning team must win a total of three sets.

    A team has a maximum of 12 players, one of which is the team leader and another the libero. The initial positions of the players in the playing area are specific. These are determined and controlled during the game by the position of the buttock in relation to the ground.

    The game begins with the service - a ball hit from the service zone at the back end of the court, with the aim of passing the ball over the net towards the opposing team. Play continues until the ball "lands" on the ground within or outside the boundaries of the court, or when the opposing team fails to return the ball in a regular way.

    (Source: en.paralympic.beijing2008.cn)