Eastern Conference

• The Eastern division of MLS consists of nine teams. These include founding league members D.C. United (Washington, D.C.); Columbus, Ohio's Columbus Crew; the New England Revolution (Foxborough, Massachusetts); Harrison, New Jersey's New York Red Bulls; and Sporting Kansas City of the similarly titled city in Kansas. The Chicago Fire (Bridgeview, Illinois) joined the league in 1997. In 2005, the Eastern Conference added Texas' Houston Dynamo, which won back-to-back championships in its first two seasons. A year later, the conference admitted its first Canadian team, Toronto FC (Toronto, Ontario). The conference's youngest member, the Philadelphia Union (Pennsylvania), joined in 2008.
  
  Of the Eastern Conference teams, D.C. United has won the most championships, acquiring three titles to complement its victory in the inaugural MLS Cup in 1996.
  
  

Western Conference

• The MLS Western Conference mirrors the nine-team structure of the Eastern Conference. Founding league members include the Colorado Rapids (Commerce City, Colorado) and California's Los Angeles Galaxy and San Jose Earthquakes. This conference also contains FC Dallas (Texas), which joined the league in 1996. In 2004, the conference expanded to include C.D. Chivas USA (out of Carson, California) and Utah's Real Salt Lake. Washington's Seattle Sounders FC entered league play in 2007, while Oregon's Portland Timbers and MLS' second Canadian team, the Vancouver Whitecaps FC (British Columbia), joined in 2009. In 2012, the league will formally admit its third Canadian team when the Montreal Impact (Quebec) enters the Western Conference.
  
  Real Salt Lake won the MLS Cup in its first year by defeating the Los Angeles Galaxy, which claimed the title in 2002 and 2005.
  
  

Reserve League

• MLS first formed a reserve league in 2004. A reserve league provides a competitive league for prospective professional players who have not yet matured enough in the sport to participate at the professional level. These leagues also help spot and groom potential talent. After struggling to raise funds for the reserve league's continuance, MLS canceled it in 2008.
  
  In 2010, MLS announced the formation of a new reserve league system. This league will receive funding from Adidas as part of that sportswear company's continued sponsorship of MLS. MLS will admit players under 24 years old. Each team in the league will form a MLS Academy Team consisting of these younger players.
  
  

North American SuperLiga

• In 2007, MLS entered into the North American SuperLiga, a bracketed tournament with teams from Primera División, a professional league in Mexico. This international competition enabled MLS to pit its top four teams against the top four teams from the Mexican league, with the goal of exposing MLS players to international levels of competition.