This is a list of professional sports leagues. A sports league is a professional body that governs the competition of its teams. They make the rules for competition and behavior and disciplines its members as necessary. This is done through a structure that varies by league. Some are made up of a board of governors that have a commissioner or president, while others are single entity organizations where the league owns the franchises and therefore does not have a board of governors. This list attempts to show those sports leagues for which all players and teams are paid to play. In other words, these players can be considered to play their chosen sport as their profession. Some leagues do not pay well enough to allow players to use them as their primary or only source of income, but because the players are paid, it is still considered professional, or semi-professional. As such, some leagues listed here may not be fully professional. (en)