International negotiations for nuclear arms control, nonproliferation, and disarmament have arrived at a critical crossroads. After decades of recurring contributions in decreasing the nuclear threat, the past decade of nuclear bargaining is associated with failure to arrive at and implement broad and lasting agreements. This trend applies to all types of nuclear diplomacy: to prevent further spread of nuclear weapons, to control existing nuclear arsenals, and to their long-term dismantlement. This downwards trend in nuclear diplomacy runs in parallel with another concerning development: The increase of warheads in most nuclear arsenals, as a symptom of the rising importance of these weapons for the nuclear armed states. This means that we are up against a significant increase in the nuclear threat due to two different but interrelated trends: a declining capacity of nuclear negotiations and an increasing number of nuclear warheads in most nuclear arsenals. The heartbeat of nuclear diplomacy is fading to the rising drumbeats of another nuclear arms race. The overarching ambition of this book is to provide remedy. Our cure consists of an injection of knowledge for the reinvigoration of nuclear negotiations. We have come together as scholars to revitalize a negotiation perspective on nuclear diplomacy. With more knowledge, we can lay the basis for more effective nuclear diplomacy and contribute to an informed discussion of how to take nuclear negotiations forward at this critical moment. The key question that we pose in this book is: What are the conditions for making nuclear negotiations effective?