[en] The research and development work done at the Central Glass and Ceramic Research Institute, Calcutta, on the various aspects of the fixation high level purex process radioactive wastes in glass for ultimate disposal has been summarised. The development studies were carried out on: vitreous matrices (glass compositions) and their physical and chemical properties; the problem of the volatilisation of Ru and Cs during glass melting and evolving methods for suppression of their volatilisation; and the problem of temperature build-up in the glass blocks during storage. On the basis of results of these studies and pot melting trials made at the Bhabha Atomic Research Centre, a waste immobilisation plant for purex process waste is being set up at Tarapur and is expected to be completed by 1977.(M.G.B.)