There is only one large city in Italy where radio-dispatched taxi service does not work, and that is Palermo. The service, established elsewhere over the last twenty years, usually consists of a group of drivers who chip in to pay for a telephone number, advertise it, and pay an operator to distribute the calls to the drivers as they patrol the city. If anyone fails to contribute, it is simple enough to retaliate by cutting off his radio. At this level, cooperation is easily enforced and trust is not an issue.

XREF: Connects to the broader theme of how self-enforcing cooperative institutions succeed or fail depending on enforcement mechanisms, likely relevant to the book's larger argument about trust and social capital.

Diego Gambetta, The Sicilian Mafia The Busi…, loc. 587