Major League Soccer 2012
MLS is the top level professional league in North America, sitting above the North American Soccer League (NASL), termed the "second division." There is no promotion or relegation between these levels although teams from both competitions compete in the US Open Cup. The Canadian teams play in the Canadian Championship, their only route into the CONCACEF Champions League (CCL).
MLS operates under a single-entity structure with teams centrally owned by the league and run by owner-operators on a franchise basis. Revenues are shared and players are contracted to MLS rather than individual teams while complex rules govern the composition of each squad. These measures, along with an annual players-draft are designed to prevent wealthy teams buying up the best talent and to deliver financial stability.
MLS is organised into Eastern and Western Conferences: teams play each other twice, home and away with additional games organised within each conference. From 2012 the top five teams in each section play off with the winners then meeting in a single match for the MLS Cup. The team with the best overall record at the end of the regular season is awarded the Supporters' Shield.
Montreal Impact become the competition's third Canadian team this season while MLS have made it known that they favour further expansion with a new franchise in New York in the future.
Logos are the property of the respective MLS franchise teams.
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Success has eluded the team since 2006, when Chicago moved into Toyota Park in Bridgeview, Illinois, a suburb of Chicago.
Chivas USA is the sister club of Mexican team CD Guadalajara, popularly known as Chivas (Goats) in Spanish. They draw support from the large Mexican-American population of Los Angeles and share The Home Depot Center with LA Galaxy.
Colorado play in Commerce City, a suburb of Denver and wear the corporate colours of Kroenke Sports Enterprises, who bought the franchise in 2007. 
"The hardest working team in America" have updated their usual all-yellow home strip to Adidas' latest, attractively simple, template. The away strip, previously black, is switched to all-white with the yoke and sleeves in yellow and black.
Representing Washington DC, the Black and Red are the most successful team in the history of professional league soccer in the US. Plans to build a stadium of their own have so far come to nothing and the team still play in the 45,600 seat RFK stadium, owned by the District of Columbia. 
Charter members of MLS (as Dallas Burn), the team was re branded in 2004 and has played as FC Dallas ever since. They moved into Pizza Hut Park in August 2005, which is situated in and owned by the City of Frisco, a northern suburb of Dallas. FC Dallas have won the US Open Cup once (1997). The club's official colours are Republic Red, Bovine Blue, Shawnee Silver and Lonestar White. That's red, white and blue then. The franchise signed their first ever sponsorship deal in June and the new shirts appeared a month later against LA Galaxy.
Houston played their games on the road until May when their brand new BBVA Compass Stadium in downtown Houston was opened. They play in orange, white and "Space City Blue" and have two stars embroidered above their crest, marking their championship wins. Their main strips are unchanged from last season but a new third strip, in deep orange and, well orange really, has been introduced to coincide with the move to their new home, which is also very orangey.
LA Galaxy won the double of MLS Cup and Supporter's Shield last year to add to their impressive haul of trophies. Despite prolonged absence through injury, David Beckham played an important role in their success alongside their second designated player, all-time Irish top goal scorer Robbie Keane, and has committed himself to a further two-year contract.
MLS's newest franchise is to all intents and purposes the former NASL team of the same name, retaining the colours, management structure and Saputo Stadium (now to be expanded with a $23m grant from the Quebec government). Big games may be played at the neighbouring Olympic Stadium.
"The Revs" are based in Foxburgh, Massachusetts but aim to draw support from throughout New England. They are owned by Robert Kraft who also owns the NFL New England Patriots team. (The names of both sides reflect New England's involvement in the American Revolution of 1776.) The team wears patriotic dark navy blue, red and white.
After the franchise was sold to Red Bull GmbH in 2006 the team underwent a comprehensive re brand. They play in the $200m Red Bull Arena, paid for entirely by the parent company in Harrison, New Jersey.
Philadelphia's colours of midnight blue and natural khaki are based on the uniforms of the Continental Army worn during the Revolutionary War and the team crest features thirteen stars, symbolising the original Thirteen Colonies. The light blue accent colour represents the colour of the flag of Philadelphia and is much more prominent this season.
Portland Timbers finished sixth in the Western Conference in their inaugural season (12th overall).
Salt Lake wear a gold star over their crest to commemorate their 2009 MLS Cup win. Last time out they finished third in the Western Conference and reached the play-off semi-finals.
San Jose Earthquakes inherited the record of San Jose Clash (now Houston Dynamo) when they were granted a franchise in May 2006. The two stars above their crest represent the MLS Cup wins won by the previous franchise in 2001 and 2003. Management is so keen to associate the current set up with its predecessors that "EST 1974" is stitched into the back of the shirts below the collar.
After finishing second in the Western Conference last season, Seattle were defeated in the play-offs by Salt Lake. They did, however, win the US Open Cup for the third season in succession.
Kansas City won the Eastern Conference last season and reached the semi-finals of the play-offs.
Despite modest performances (eighth in the Eastern Conference in 2011), Toronto's home support ensures that financially at least, the franchise is consistently profitable. As winners of the Canadian Championship for the third successive season, Toronto qualified for the CCL once again.
Vancouver Whitecaps found it hard in their first MLS season, finishing bottom of the Western Conference last season.