Major League Soccer (MLS) is a professional soccer league with teams from the United States and Canada. It is sanctioned by the professional divisions of both the United States Soccer Federation (USSF or U.S. Soccer) and the Canadian Soccer Association (CSA), which are both members of FIFA. In 2007, The league comprised of 13 teams are split into two conferences, the Western Conference has six teams, while the Eastern Conference has seven, including the league's newest addition, Toronto FC. The season typically runs from April to November each year.