During the war years the techniques for electromagnetic separation of radioactive nuclides have made great progress. Ever since then further improvements have been accomplished to separate stable nuclides and in more recent years special attention has been given to the problem of separating radioactive nuclides, especially in con nection with spallation and high energy fission studies. This poses slightly different problems, as the amounts of radioactive material may be very small indeed, highly diluted and the whole separation procedure has often to be a very rapid one, as some of the nuclides have a very short half-life. . On quite a number of the bigger machines very valuable operating experience has been gained and it was, therefore, a very good idea to hold a symposium’ covering all the aspects of electromagnetic separation, where technicians could discuss the recent advances in this wide field. It is to be welcomed that at this symposium all aspects were discussed, from the details of vacuum systems, as well as sub jects like magnets, ion sources, scattering mechanisms, to the health physics problems connected, for example, with the electromagnetic separation of plutonium, as well as applications of mass separation. These proceedings are, therefore, essential for all those who do work in this field or contemplate to enter into it. Vienna, May 1961.