Serie A is the world's second-strongest national league according to IFFHS and has produced the highest number of European Cup finalists with Italian clubs having reached the final of the competition on a record 27 different occasions, and winning the title 12 times.
Serie A is ranked fourth among European leagues according to UEFA's league coefficient, behind La Liga, Bundesliga and Premier League, which is based on the performance of Italian clubs in the Champions League and the Europa League during the last five years. Serie A led the UEFA ranking from 1986 to 1988 and from 1990 to 1999.
In its current format, the Italian Football Championship was revised from having regional and interregional rounds, to a single-tier league from the 1929–30 season onwards. The championship titles won prior to 1929 are officially recognised by FIGC with the same weighting as titles that were subsequently awarded. However, the 1945–46 season, when the league was played over two geographical groups due to the ravages of WWII, is not statistically considered, even if its title is fully official. All the winning teams are recognised with the title of Campione d'Italia ("Champion of Italy"), which is ratified by the Lega Serie A before the start of the next edition of the championship.
The league hosts three of the world's most famous clubs as Juventus, Milan and Internazionale, all founding members of the G-14, a group which represented the largest and most prestigious European football clubs; Serie A was the only league to produce three founding members. More players have won the coveted Ballon d'Or award while playing at a Serie A club than any other league in the world - although Spain's La Liga has the highest total number of Ballon d'Or winners including the FIFA Ballon d'Or.
Milan is the third club with the most official international titles in the world, with 18. Juventus, Italy's most successful club of the 20th century and the most successful Italian team, is tied for fourth in Europe and eighth in the world in the same ranking. The club is the only one in the world to have won all possible official continental competitions and the world title. Internazionale, following their achievements in the 2009–10 season, became the first Italian team to have achieved a treble. Juventus, Milan and Inter, along with Roma, Fiorentina, Lazio and Napoli, are known as the Seven Sisters of Italian football.
Since Italy is currently rated fourth in Europe in terms of club football ratings, the top three teams in the Serie A qualify for the UEFA Champions League (from the 2012–13 season). The top two teams qualify directly to the group phase, while the third-placed team enters the competition at the playoff qualifying round and must win a two-legged knockout tie in order to enter the group phase. Teams finishing fourth and fifth qualify for the UEFA Europa League tournament. A third UEFA Europa League spot is reserved for the winner of the Coppa Italia. If the Coppa Italia champion has already qualified for the major European tournament by placing in the top three of Serie A, the third UEFA Europa League spot goes to the sixth-ranked team in Serie A. If both Coppa Italia finalists finish among the top five teams in Serie A, the sixth-ranked team in Serie A is awarded the UEFA Europa League spot. The three lowest-placed teams are relegated to Serie B.