Lega Pro Seconda Divisione is the name of the fourth highest football league in Italy. It consists of 54 teams, divided geographically into three divisions of 18 teams each.
Until 2008 the league was known as Serie C2.
Before the 1978-79 there were only three leagues of professional football in Italy, the third being Serie C. In 1978, it was decided to split Serie C into Serie C1 (the third highest league) and Serie C2. Upon its inception in 1978-79, Serie C2 consisted of four divisions, however, that number was reduced to three since the start of the 1991-92 season.
During the regular season, teams play only other teams in their own division. Each opponent is played twice, once at home and once away, for a total of 34 matches. Games are scheduled such that in the first 17 matches, every opponent is played once. In the last 17 matches, the same opponents are played in the same order with the only difference being that the venue changes.
In each division, two teams are promoted to Lega Pro Prima Divisione, and three teams are relegated to Serie D. In total, the league promotes 6 teams to Prima Divisione and relegates 9 teams to Serie D.
The team finishing first in the regular season is directly promoted to Prima Divisione, while teams placing 2nd to 5th are entered into a play-off semi-final for the chance of gaining the second promotional spot for that particular division.
In the play-off phase that takes place after the regular season is completed, in each division the team placed 2nd will play the team placed 5th, and the team placed 3rd will play the team placed 4th in two double-leg promotional semi-final series with the higher classified team having home field advantage in the second leg. In case of an aggregate tie score, the away goals rule is not used, and the higher classified team is declared the winner without extra time being played nor penalty kicks being taken. The winning teams advance to the final in another double-leg series with similar rules. The only difference being that if an aggregate tie exists at the end of the second match, extra time is played. If the tie persists, again the higher classified team is declared the winner and no penalty kicks are taken. The winner becomes the second team promoted for that particular division to Prima Divisione.
The team finishing last in the regular season is directly relegated to Serie D, while teams placing 14th to 17th are entered into a play-out. There is only one round in the play-outs. In each division the team placed 14th will play the team placed 17th, and the team placed 15th will play the team placed 16th in a double-leg series with the higher classified team having home field advantage in the second leg. In case of an aggregate tie score, the rules are exactly the same as those for the promotional semi-finals. The two winning teams remain in Seconda Divisione while the two losing teams become the second and third teams relegated for that particular division.
These are the 307 clubs which took part to the 30 Serie C2 editions played from 1978-79 to 2007-08 and to Lega Pro Prima Divisione from 2008-09 onwards. Bolded teams compete in current season.