This thesis is a qualitative case study of counterterrorism in Brazil. Special focus is put on law 13.260, commonly referred to as “the anti-terror law”, enacted in 2016. Theoretically my focus is on the applicability of the common notion of counterproductivity as used in the theoretical literature on counterterrorism. Based on data from the Global Terrorism Database I have classified all the confirmed cases of terrorism in Brazil between 1970-2018. Terror attacks from people/organisations with international ties have amounted to 10, and the number of lives claimed in such attacks are 2. In general,the threat of terrorism in Brazil is less acute than in many other countries. What stands out in law 13.260 is that it does not state that actions must be politically motivated in order to be classified as terrorist acts. This is because of the fear that the law could otherwise be targeted towards social movements. Furthermore, the documentation about the law and its background shows that it was the result of pressure from abroad rather than any need perceived among the Brazilian public, politicians, or military. I conclude that Brazil´s counterterrorism legislation is not per se counterproductive, however patterns of Military Police actions used in the past can return and cause it to be so. I also conclude that the notion of counterproductivity was useful for systematising the Brazilian experience in the case study.