The Stimson Center in the US has published in August a book containing an analysis of how drones relate to various international regulatory regimes. This report offers a particular focus on the international Arms Trade Treaty (ATT) and examines the ways in which drone transfers and use are regulated by the ATT. For the purposes of this paper, references to drone(s), unmanned aircraft, and unmanned aerial vehicle(s), or UAV, will be made interchangeably. It says that UAV, more commonly referred to as drones, have become a mainstay of military operations around the world. They can be fitted with, or used as, weapons, or used as surveillance or reconnaissance types with cameras, sensors or sophisticated electronics. Governments may be more willing to resort to the use of lethal force via armed drones, thereby lowering the threshold for engaging in armed conflict. It says that new technological developments – focused on miniaturising and swarming, for example – may lead to an expansion of demand and of drone capabilities. These new technological developments may also present additional challenges related to use and control. Regardless of their type, as drones continue to proliferate around the world, it will be important for States to assess the impact of increasing drone use and understand the mechanisms in place that regulate the transfer and use of drones. The report explains that the ATT is the first treaty to establish legally binding standards for regulating the global trade in conventional weapons. The ATT was adopted by the UN General Assembly in April 2013, entered into force in December 2014, and aims to increase transparency and promote responsibility and accountability in international arms transfer decisions. The ATT covers 8 categories of conventional weapons: battle tanks, armoured combat vehicles, large-calibre artillery systems, combat aircraft, attack helicopters, warships, missiles and missile launchers, and small arms and light weapons. Though the text of the ATT does not provide definitions for these categories of weapons, Article 5.3 requires that national definitions of these weapons systems “not cover less than the descriptions used in the UN Register of Conventional Arms” at the time of the treaty’s entry into force. It argues that, although the ATT does not explicitly reference drones within its scope, the treaty does implicitly apply to drones. 53 UN Member States, including the US, had signed up to the declaration and agreed to begin a process to develop global standards on export and subsequent use of armed drones, and the US led a small group of states to build on the joint declaration and draft more detailed, politically-binding standards for the transfer and use of drones. However, these efforts have stalled in the first 18 months of the Trump administration.