The presence of the mafias in Italy is an irrefutable fact. Surprisingly, however, a relatively small number of studies and publications have attempted to measure the presence of mafias on the Italian territory. This is remarkable, because measurements are fundamental in the perspective of supporting the law enforcement activity against the mafias. Probably, better data and information sharing, and therefore better measurements, could effectively contribute to Italy’s efforts to prevent mafias or to enforce the law against them. The aim of this article is to partially fill this gap and present the Mafia Index (MI hereinafter), a composite index measuring the presence of mafias at the provincial level in Ital
