The literature on arms control and disarmament is replete with studies demonstrating the numerous difficulties in negotiating agreements for the control or elimination of nuclear weapons. These studies stress the time consumed during negotiations, the complexity of the emerging agreements, the trade-offs required to achieve agreement, the political difficulties of treaty ratification, and the alleged advantages of alternative approaches to arms control and disarmament not involving treaties. This essay examines whether treaties and negotiations are in fact dispensable in achieving agreed multilateral disarmament objectives. It surveys recent multilateral efforts in the field of nuclear disarmament and identifies six basic criteria that enjoy broad international support as standards for assessing the merits of disarmament agreements. The essay concludes that tacit understandings and other informal political arrangements offer no substitute for legally-binding treaty obligations. This conclusion leads to several implications affecting the conduct of multilateral negotiations, and the kinds of institutional support required in the negotiating process and for the maintenance of key commitments by the relevant multilateral regimes.