Serie B is the name of the second highest football league in Italy. It consists of 22 teams. The championship is often called the cadetti, which means 'juniors' or 'cadets', or campionato cadetto.

Serie B was composed of 20 teams until the 2002-2003 season. It was enlarged to 24 teams for the 2003-2004 season due to legal problems relating to Calcio Catania relegation. The league reverted to 22 teams for the 2004-2005 season, while Serie A expanded from 18 to 20 teams.

During the regular season, each team plays 42 games - 2 each against every opponent. In Italian football, a true round-robin format is used - In the first half of the season, called andata, each team plays once against all its opponents, a total of 21 games. In the second half of the season, called ritorno, each team will play the same teams in the exact same order, the only difference being that a home game played in the first half will be an away game with that same team in the second half, and vice versa.