Foreign law is considered in this essay not as the "applicable" law according to the rules of international private law or to the will of the parties, but as a model of adjudication for the Italian judge. The author analyses some of the cases - in historical perspective and in the present situation - in which the Italian judge has taken foreign rules, foreign decisions and foreign ways of reasoning into account to help improve the solution of a case. Foreign law is also used to import rules concerning persons (e.g. the trust or the Anstalt) or types of contracts (e.g. engineering, franchising, or leasing) into the Italian legal system. Moreover, foreign law underlies the way that many EU Directives and many general principles governing international commercial contracts are drafted.