[en] In this document, a state-of-art review of dispersion models relevant to local, regional and global scales and applicable to radionuclide discharges of a continuous and discontinuous nature is presented. The theoretical basis of the models is described in chapter 2, while the uncertainty inherent in model predictions is considered in chapter 6. Chapters 3 to 5 of this report describe a number of models for calculating atmospheric dispersion on local, regional and global scales respectively