Legislative Decree no. 286 of 25th July 1998 "consolidate act enacting provisions governing immigration and alien status"
Article 26 c. 3 provides that foreign nationals wishing to pursue professional activity in Italy, must demonstrate:
- to have sufficient financial resources to start the activity he wishes to pursue in Italy;
- to meet the requirements contained in the legislative, regulatory or administrative provision in     force in Italy to pursue the profession, including those, on demand, which confer the holder the     right to register himself in a Register or public register;
- to hold a certificate, not older than three months, issued by those competent authorities     stating that such person is allowed to pursue the activity he intends to

Presidential Decree no. 394 of 31st August 1999 "Regulation implementing the consolidated act enacting provision governing immigration and alien status, pursuant to section 1, c. 6 of the Legislative Decree no. 286 of 1998"
Article 49, c.1, provides that foreign nationals, regular staying within Italian territory, wishing to register themselves with Orders/ Colleges/Registers held by competent administrations, according to article 3, c. 4 Legislative Decree no. 286 of 1998, holding professional qualification obtained in non European countries, must submit a professional recognition application that allows them to pursue the activity they intend to.

Presidential Decree no. 334 of 18th October 2004 "Regulation amending and supplementing Presidential Decree no. 394 of 31st August 1999 in matters of immigration"