The project focuses on the sustainability of welfare systems in EU countries in the face of ageing and demographic uncertainty. The main innovation is to bring new quantifications of demographic uncertainty into economic & social analysis of the effects of population ageing. The main tools are general equilibrium models with overlapping-generations structure. It compares the welfare systems in participating countries and look for systems and rules that perform well under uncertainty. The project also attempts to improve current policy instruments, and design new, to better cope with demographic uncertainty, and evaluate their performance with model simulations. Guidelines for future development for both economic and demographic models will also be formulated. The project partners are ETLA, Finland; CPB, the Netherlands; NIESR, the UK; FEDEA, Spain; CEBR, Denmark; CEPII, France; University of Würzburg, Germany and the FPB, Belgium.