The UEFA Europa League comprises three qualifying rounds, a play-off round, a group stage and five knockout rounds.
In matches in the three qualifying rounds and the play-offs, clubs play two matches against each other on a home-and-away basis. The club which scores the greater aggregate of goals qualifies for the next round, with away goals and then penalties used to determine the winner in the event of a draw.
The 38 play-off round winners join the ten losers from the UEFA Champions League play-offs. The clubs are split into 12 groups of four teams, playing home and away against each of their pool opponents between September and December. Two sides from each section advance, proceeding into the round of 32 alongside eight third-placed teams from the UEFA Champions League group stage.
From the last 32 until the semi-finals, clubs play two games against each other on a home-and-away basis with the same rules as the qualifying and play-off rounds applied. In the last 32, group winners and the four third-placed sides from the UEFA Champions League with the best records are seeded, guaranteeing they will play the second leg at home. Teams from the same group or the same association cannot be drawn together. From the round of 16 onwards the draw is free.
The final is decided by a single match, which this season will be played at the National Stadium, Bucharest on Wednesday 9 May.
Further details, including the criteria for separating teams that finish level on points in a group, can be found in the official competition regulations.
The 2012 UEFA Europa League final will be staged at Bucharest's National Stadium.
• The UEFA Executive Committee took the decision in January 2009 to award the 2012 showpiece to the venue, which is being built on the site of the former National Stadium. The arena will include a fully retractable roof and have a capacity of 55,200 with the potential for expansion to 63,000.
• The arena's predecessor closed its doors in November 2007, Romania bowing out in style with a 6-1 victory against Albania in UEFA EURO 2008 qualifying. The stadium hosted national-team games and domestic cup finals, as well as being home to FC Steaua Bucureşti and FC Dinamo 1948 Bucureşti and a venue for music concerts.
• Perhaps the stadium's most famous night came in 1983 when Romania beat world champions Italy in UEFA European Championship qualifying, László Bölöni scoring the only goal midway through the first half.
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