  It is estimated that Italian Mafias registered 135 billion euros in profits
only in 2010. Part of this huge amount of money, coming mostly from the drugs,
prostitution and arms illicit markets, is often used to invest into legitimate
private economies. As a consequence, the affected economies destabilise, become
entrenched with violent forms of competition and are bound to stagnation.
Nonetheless, few are the attempts to uncover the patterns followed by criminal
organisations in their business ventures. The reason lays mostly in the poor
availability of data on criminal activity, or in the highly risky task of
gather it.
  This paper partially fills this gap thanks to access to information about the
Sicilian Mafia in a city. More specifically, it tries to analyse the nature and
extent of criminal infiltration into the legitimate private economy of the
case-study using network techniques. The research demonstrates that sectors
with a high degree of centrality and comprising fewer firms are the most
vulnerable to this kind of security threat. It also shows that centrality is
also the key criterion that makes a firm sensitive to infiltration, provided it
belongs to a susceptible economic sector.
