This chapter gives an overview of how the phenomenon of illicit trafficking of cultural property has morphed into an international security issue with ISIS at its centre, and the way in which the international community is trying to address this new threat through legal instruments. Section 1 provides a brief timeline of looting of cultural property in history that shows how this practice has always taken place, but for different motives. Section 2 uses the infamous looting of the National Museum of Baghdad of 2003 as a case-study to illustrate how the activity of looting cultural property acquired a difference nuance with the rise of fundamentalist terrorist groups, turning it into a new international security issue. Section 3 describes how the illicit traffic of antiquities works in Syria and in Iraq, and the role that is known ISIS plays in it. Section 4 explains the reach of the different legal instruments that pre-existed this phenomenon or have been put into place to tackle this new threat to international peace and security. Finally, section 5 looks at possible venues for prosecuting persons involved in this transnational phenomenon.