|Paralympic Games on the BBC|
|Venue: Rio de Janeiro, Brazil Dates: 7-18 September Time in Rio: BST -4|
|Coverage: Follow on BBC Radio 5 live and via live text commentary|
How does it work?
Sitting volleyball is played under similar rules to the standing game but with a few alterations.
The net is lowered to ground level as the players hit the ball over the net sitting down. The net height for men is 1.15m and 1.05m for women. For a hit to be legal, all players must keep their pelvis in contact with the floor and unlike Olympic volleyball, blocking of the serve is allowed.
Teams are made up of six players and all physical impairments are included in this game. However, only two players classed as 'minimally disabled' may feature on court at any one time - minimal impairments include anterior cruciate ligament injuries and missing fingers.
All other players are classed as 'disabled' where the main impairment group are usually amputees.
The first team to 25 points wins a set, but they must win by two clear points. The first team to win three sets is the winner. A maximum of five sets are played. If a match goes to a deciding fifth set, the first team to 15 points and with a two-point advantage wins.
Who are the British medal hopes?
Great Britain did not qualify a men's or women's team for the Rio 2016 Paralympics.
A low finish at the 2014 World Championships meant they were unable to feature in the 2015 European Championships, which also served as a qualifying event.
Who are the other challengers?
In the men's event, Bosnia & Herzegovina are the reigning world and Paralympic champions but Iran are specialists in this sport having won five Paralympic titles since 1988.
In the women's event, China are the defending world champions and have won the last two Paralympic titles against the USA, who will be hoping to turn silver into gold at their third opportunity in Rio.
Did you know?
One player on court is known as the 'libero' and they wear a different colour shirt to the rest of the team because they specialise in defensive tactics.
ParalympicsGB London 2012 medals