Nuclear energy is a proven low-carbon technology that can provide the dispatchable electricity needed to stabilize national grids that have increasing shares of renewables. Other nuclear technologies are applied in medicine, industry, and research to provide benefits to both developed and developing countries around the world. All nuclear applications result in the production of radioactive wastes. The safe and secure management and disposal of these wastes are essential for the use of these technologies to be sustainable. The expertise and the funding required must be available to all countries employing them. For some countries, this can be ensured more easily (or only) by implementation of multinational approaches. In particular, implementing geological disposal facilities (GDFs) for radioactive wastes presents a special challenge; these must be available to nuclear power countries, and they are also a necessity for nonnuclear power nations employing other technologies that produce small quantities of long-lived radioactive wastes. In all waste management programs, implementing a GDF is a challenging task requiring sensitive stakeholder interactions and significant funding. For small or new programs, the societal and economic challenges are both large. Multinational repositories (MNRs) — GDFs disposing of radioactive wastes from several countries — can provide a solution. This paper briefly illustrates nuclear technologies that give rise to radioactive wastes. It then reviews initiatives devoted to promoting multinational cooperation, and in particular in MNR developments, both globally and specifically in Europe. Several national programs have adopted the MNR concept as part of a so-called “dual track” approach in their national waste management strategy. An important recent organizational development is the transition of the European Repository Development Organization Working Group into a formal legal entity, the ERDO Association, with dedicated facilities and personnel. By supporting MNR development, we can work toward a world in which all countries can benefit from nuclear technologies, free from safety, security, or environmental concerns related to the disposal of their radioactive wastes.