Participants coming from EU nations and citizens of USA, Canada, Australia and New Zealand, do not need visas to enter Italy. Most NON-EU citizens (and participants from other countries) will need a visa and, sometimes, either a declaration or a permit of stay to formalize their visit in Italy.
As visa regulations are continuosly evolving, we strongly recommend you to consult the official website of the Italian Ministry of Foreign Affairs (www.esteri.it/visti/home_eng.asp) for updated and detailed information for foreigners regarding entrance visas for Italy and permits of stay. Information is offered in English and other languages.
The application for a visa must be done at the Italian Consulate or Embassy in your country of origin or where you have permanent residence, at least 3 months prior to the congress.