1 Next Generation Neutron Sources

The overall theme for this issue of MRS bulletin is New Frontiers in the Application of Neutron Scattering to Materials Science. The present article is devoted to the next generation of neutron sources tha t will provide an unprecedented jump in performance. The size ( ~ 50-100 hectares) and cost (1,5 – 2 millions $) of these facilities are such that only 3 of them are envisaged world-wide, the two construction projects, the spallation neutron sources in the US (SNS) and in Japan (J-PARC), and the European proposal for a spallation source (ESS) which is still awaiting a decision to start construction