Second only to the Champions League in European club football, the Uefa Cup introduced a league section in the 2004-05 season.
Two qualifying rounds decide which 40 teams play in a new group stage, with each group containing five teams.
Each club plays two home games and two away games and the top three teams go through to the knock-out stages.
They are joined in that round by the clubs which finished third in their respective groups in the Champions League.
After that the competition stays a knock-out event, with teams drawn against one other team who they play home and away.
The final is one of the last games of the season and is played over one leg in a neutral venue - that is a ground that doesn't belong to either of the finalists.