Deep geological repositories of radioactive waste are designed and licensed based on a model of long-term safety which does not require the active presence of man. During the period of stepwise development of such repositories, reversibility of decisions and retrievability of the waste are widely thought to be beneficial. Reversibility and retrievability are not requirements for long-term safety. They are instead about implementing a process that responds to ethical and precautionary obligations without compromising safety. How are the concepts of reversibility and retrievability understood in the various nuclear countries? How do they appear in national waste management legislation, regulation and operational programmes, and how can they be implemented? The “R&R” project of the OECD Nuclear Energy Agency (NEA) culminated in an International Conference and Dialogue on Reversibility and Retrievability in December 2010. This open meeting brought together regulators, policy makers, elected officials, experts in social sciences, and representatives of civil society and stakeholder groups in addition to waste management professionals. These proceedings include the texts of 50 presentations and the “International Retrievability Scale” – a tool to support dialogue with stakeholders and to help establish a common international framework.