The first tournament was held in 1947. Since then a team from the United States has won the series 25 times, but only six of those titles have come in the last 25 years. Teams from the Far East have dominated the event for the last quarter century, winning 17 of 25 titles. Each team will play the other three teams in their pool once, with the top two teams from each pool advancing to the semifinal round on Thursday. The winners of each semifinal game meet in Saturday afternoon's championship game.
All games are six innings long, with the possibility of extra innings.