Impurity control and He-ash removal in magnetically confined plasmas are still major obstacles on the road towards the technological realization of fusion power. To review and evaluate experimental and theoretical progress in this field, about 70 scientists from ten countries met under the auspices of the IAEA at the Max-Planck-Institut für Plasmaphysik at Garching, Federal Republic of Germany, from 6 to 10 July 1981.