Drone technology is not only a game changer, it also triggers obligations. If we recast our perception of drones as solitary planes to one of a comprehensive technology with extensive surveillance and control capabilities, we encounter new and crucial legal implications of the use of drones in armed conflict. To make its argument, this article first places the surveillance and control capabilities of drone technology within the context of the European Convention of Human Rights. The European Court of Human Rights has found that the Convention applies in a number of cases where a member state exercised control and authority over persons or territories outside Europe. The article argues that this may affect the legal basis for European states that employ drones for attacks. The second part of the article examines the implications of the surveillance capabilities of drone technology for the principle of precaution in international humanitarian law (IHL). The argument is that drone technology offers an effective precautionary measure, which may trigger precautionary obligation across all weapons systems. If a state possesses drone technology, and if the deployment of this technology may potentially reduce unnecessary harm from armed attacks, including shelling, the state is obliged under IHL to employ this technology for precaution. In addition to identifying so far overlooked legal implications arising from the employment or availability of drone technology for attack in armed conflict, the article raises the more general question of how the laws of armed conflict should be applied in an era of total surveillance.