Organised crime in Italy is dominated by four mafia clans: Sicily's Cosa Nostra; the Camorra around Naples; Calabria's 'Ndrangheta; and the Sacra Corona Unita, in Puglia.
The Italian authorities have hit the Cosa Nostra hard in recent years, says the BBC's Mark Duff in Milan, but other groups maintain their grip and have seen their influence spread.
The global economic downturn has also thrown up fresh money-making opportunities for the mafia - such as lending cash to credit-starved businessmen.