Dial 113 for general emergencies. Dial 112 for the carabinieri police, 118 for an ambulance, 115 for the fire department, and 803-116 for car breakdowns (a pay towing service).
Italy is a remarkably safe country. Aside from pickpockets, there is little to fear. Violent crime is rare, and although women (especially young foreign women) may get a lot of attention, it’s mostly harmless. Italians do tend to drive aggressively, so be attentive behind the wheel.
On crowded buses, especially the No. 64 (see Pickpocket Bottlenecks), the metro, and around train stations and other areas ...