The PantheonRome has a large and vibrant expatriate community. If you're considering joining them, it pays to do plenty of research in advance. Visit the city a few times to get a feel for the place.
Think about what you're going to do for a living (a lot of people come to Rome and work as tour guides or teach English, but that can wear a little thin after a few years), where you're going to live in Rome, what your social life will be like... and what you'll do if it all goes wrong!
Legal requirements for living in Italy
The legal requirements for expatriates living in Rome (and Italy as a whole), vary according to where you're coming from.
Citizens of EU countries can theoretically waltz in as and when they like, but Italian law still requires them to have special permission to live in the country. Americans, or people coming in from other countries outside the European Union, things may be a little more complicated. Either way, it's a good idea to consult a legal expert, or at least your consulate, if you want to be sure of your likely status. Now more than ever, immigration in Italy is a strange, murky area.
Whatever your nationality, you will likely need to get hold of a permesso di sogiorno (also known as a carta di soggiorno) if you're planning to stay long in Rome. More information on the permesso.