This paper argues that pursuing negotiations in good faith on effective measures for nuclear disarmament is a legal obligation, not a foreign policy option. Drawing on the New Agenda Coalition paper of April 2014, which identified some pathways by which nuclear disarmament might be pursued, this paper identifies and analyzes international legal issues raised by each of those pathways. The paper concludes by explaining why legal analysis and discussion are important even in the absence of a settled political commitment to nuclear disarmament.