By Decree Law 7/2015, converted with amendments by Law 43/2015, we established the “National Anti-Mafia and Counterterrorism Prosecutor” and we introduced new types of offenses more suited in fighting the dynamic reality of jihadism. This is the latest response to terrorism. Terrorism is a very complex and intricate matter, innately conditioned by emergency and urgency. In the last fifteen years the matter has been affected by two reforms, in 2001 and 2005. The publication deals with the whole evolution of the legislation of terrorism, but the added value of the work is the second part, purely “operational”, dedicated to professionals and people interested in the phenomenon from a practical perspective. It describes court cases in which counter-terrorism laws have recently found application and, thanks to the exemplifying modules, the main investigative instruments introduced by the most recent reforms are described, such as preventive bugging, investigation interviews, undercover activities and the expulsion of foreigners for the purpose of preventing terrorism.