Federation. There are currently 12 club members of the league. All participants get approved by the Premier League General Assembly. Each club fields each team for senior competitions, and competitions for under 21 and under 19 teams (three teams). A club is required to have a stadium (registered with FFU) and an education and training facility (or center). A club is also obligated to finance its own youth sports institution and a complex scientific-methodical group as well as to own and finance a number of youth teams. A Premier League club needs to ensure participation of at least four youth teams (ages groups between 14 and 17) in the Youth Football League of Ukraine. A club cannot field more than one team for a certain competition. All club's staff members (coaches, physicians, massage specialists) have to be contracted and be UEFA licensed. All coaches should have A-diploma, while head coaches – PRO-diploma. Football players are listed in "A" and "B" rosters. "A" roster contains no more than 25 players, while "B" roster has unlimited number of players no older than 21 who have professional contracts or agreements for sports training. The 25-players "A" roster includes the number of slots allotted for players developed by the club. During breaks in competitions in summer and winter there are two periods for registering players. Beside the main championship among senior teams, the Premier League also organizes youth championship which was adopted from the previous Vyshcha Liha championship of doubles (reserves). Since 2012 there was added another competition for junior teams, so the original youth championship was renamed into the Championship of U-21 teams and the new competition was named as the Championship of U-19 teams. Unlike the Championship of U-21 teams, in the Championship of U-19 teams beside all of the Premier League clubs' junior teams, there also compete teams of some lower leagues' clubs. The league's championship among senior teams is conducted by manner of the round robin system in two cycles "fall-spring" with one game at home and another at opponent's field with each participant. A competition calendar is formed after a draw that is conducted based on the Premier League club rankings. The calendar of the second cycle repeats the first, while hosting teams are switched. There should be no less than two calendar days between official games of a club. All games take place between 12:00 and 22:00 local