The BBL was introduced by Cricket Australia in 2011 to replace the Twenty20 Big Bash, which was a tournament between six state-based teams. The BBL is played by eight city-based franchises.
Each team plays the other at least once in the league stage; until now, each team played every other team twice. This will change in the 2017-18 edition, when each team will play two more games. Teams are allowed two overseas players in their squad, and the tournament usually attracts top players from West Indies and England.