This publication is concerned with radioactive waste that requires geological disposal. It discusses the partnership arrangements necessary for the development of a multinational repository for disposal of this waste, but it also emphasizes that countries should not rely solely on a multinational solution and should in addition have coherent national plans for disposal (a dual track strategy). The publication focuses on multinational approaches based on the IAEA scenario for cooperation among countries in joint projects for the establishment of a shared geological repository. It describes the phased approach that would be needed, indicating the decision processes to be undertaken by partners in the multinational project, both within a national context and in the scope of the joint endeavour. It highlights a wide range of legal and institutional aspects, including the contractual obligations among partners, the economic and financial arrangements, liabilities, nuclear security, regulatory and legislative aspects, waste transportation arrangements, and social issues. It also addresses the uncertainties and risks involved in the implementation of a multinational repository.