Within the framework of this Thematic Unit, the multidimensional phenomenon of international terrorism will be approached from a sociological, forensic and legal point of view. Reference will be made to the historical development of the phenomenon and emphasis will be placed on the problem of the definition and the link with other forms of organized crime. The various aspects, in particular the contemporary forms of international terrorism and the methods and means of action used by terrorists (particularly in the context of terrorist groups) will be studied. International efforts to combat terrorism at a legal level (international conventions, UN Security Council resolutions, etc.) will also be examined, while particular reference will be made to the link between terrorism and other forms of criminal activity. Finally, the impact of counter-terrorism measures on human rights and the rule of law will be examined, with reference to important court rulings that approach and delineate the relationship between security and human rights.