International treaties:
Please be aware that there might always be income tax and social contributions issues in case of work activities carried out by non EU citizens on the Italian territory.
Before any work activity of a non EU citizen in Italy it is very important to study before all the international relevant treaties existing between the Italian Republic and the involved country(ies) in order to check if there is a tax treaty for the avoidance of double taxation or a social security agreement, evaluate the costs and plan all the compulsory steps to be done.