Armed drones pose a major threat to the general prohibition on the inter-state use of force and to respect for human rights. On the battlefield, in a situation of armed conflict, the use of armed drones may be able to satisfy the fundamental international humanitarian law rules of distinction and proportionality (although attributing international criminal responsibility for their unlawful use may prove a significant challenge). Away from the battlefield, the use of drone strikes will often amount to a violation of fundamental human rights. Greater clarity on the applicable legal regime along with restraints to prevent the further proliferation of drone technology are urgently needed. Keywords: armed conflict, direct participation in hostilities, drone, human rights, international humanitarian law, law enforcement, targeted killing, unmanned aerial vehicle.