Abstract: The Treaty on the Prohibition of Nuclear Weapons (TPNW) was adopted by the United Nations in July 2017 with the support of nearly two-thirds of the international community, despite opposition between nuclear weapon states and nuclear umbrella states on how to proceed with nuclear disarmament. Although the TPNW’s preamble details its relationship with pre-existing treaties, a number of problems have been pointed out vis-à-vis the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Additionally, analysis of the issues identified in the TPNW negotiations by the nuclear weapon states and the nuclear umbrella states suggests that they can be roughly aggregated into: i. The issue of the involvement of nuclear weapon states, ii. Concerns about the division of the international community, iii. Nuclear deterrence considerations, iv. Awareness of an increasingly severe international security environment, v. Warning about the risk of weakening the NPT system (concerns about compatibility with existing treaties), and vi. Inadequacies in verification mechanisms. The challenge for nuclear arms control and disarmament in the era of TPNW discussions is to find answers for these issues. It will become ever more important to consider the essential issues around nuclear deterrence and nuclear disarmament in order to facilitate constructive consensus-building among all concerned parties, looking ahead to the 2020 NPT Review Conference. Full text available here.