[en] For nuclear facilities, decommissioning is the final phase in the life-cycle after siting, design, construction, commissioning and operation. It is a complex process involving operations such as detailed surveys, decontamination and dismantling of plant equipment and facilities, demolition of buildings and structures, and management of resulting waste and other materials, whilst taking into account aspects of health and safety of the operating personnel and the general public, and protection of the environment. Careful planning and management is essential to ensure that decommissioning is accomplished in a safe and cost effective manner. Guidance on organizational aspects may lead to better decision making, reductions in time and resources, lower doses to the workers and reduced impact on public health and the environment. The objective of this report is to provide information and guidance on the organization and management aspects for the decommissioning of large nuclear facilities which will be useful for licensees responsible for discharging these responsibilities. The information contained in the report may also be useful to policy makers, regulatory bodies and other organizations interested in the planning and management of decommissioning. In this report, the term 'decommissioning' refers to those actions that are taken at the end of the useful life of a nuclear facility in withdrawing it from service with adequate regard for the health and safety of workers and members of the public and for the protection of the environment. The term 'large nuclear facilities' involves nuclear power plants, large nuclear research reactors and other fuel cycle facilities such as reprocessing plants, fuel conversion, fabrication and enrichment plants, as well as spent fuel storage and waste management plants. Information on the planning and management for decommissioning of smaller research reactors or other small nuclear facilities can be found elsewhere. The report covers organizational aspects of decommissioning and describes factors relevant to the planning and management of a decommissioning project. It identifies the general issues to be addressed and provides an overview of organizational activities necessary to manage a decommissioning project in a safe, timely and cost effective manner. There are a number of facilities that present special cases and include those which have undergone a major accident as well as uranium mines and mills and radioactive waste repositories. These facilities are not dealt with in this report. This report is structured as follows. Section 1 contains background information, objectives and scope of the document. In Section 2 considerations important for decommissioning management are discussed which could affect the organization. Section 3 deals with the management for active phases of decommissioning and provides a discussion on the organization of the decommissioning management team. Section 4 gives an overview of the decommissioning planning and approval process. Section 5 provides information on quality assurance issues relevant to decommissioning. Management of decommissioning wastes is briefly discussed in Section 6. Responsibilities and qualifications of the decommissioning management team are dealt with in Section 7. Conclusions and recommendations are given in Section 8. The report is supplemented with references, Appendix I giving details on recent experience on data management, a glossary, and national annexes, some of which indicate how the principles set out in the main report are to be utilized in different countries, and some of which are real examples of arrangements used in decommissioning projects. A list of drafting and reviewing bodies is also included