This book arose from two research projects, ‘Demographic Uncertainty and the Sustainability of Social Welfare Systems’ (DEMWEL) and ‘Uncertain Population of Europe’ (UPE).

DEMWEL was carried out between January 2003 and March 2006 by research teams from the following nine institutes: CEBR, the Centre for Economic and Business Research, Copenhagen, Denmark; CEPII, Centre d'Etudes Prospectives et d'Informations Internationales, Paris, France; CEPS, the Centre for European Policy Studies, Brussels, Belgium; CPB, the Netherlands Bureau for Economic Policy Analysis, The Hague, The Netherlands; ETLA, the Research Institute of the Finnish Economy, Helsinki, Finland; FEDEA, Fundacion de Estudios de Economia Aplicada, Madrid, Spain; FPB, the Belgian Federal Planning Bureau, Brussels, Belgium; NIESR, the National Institute for Economic and Social Research, London, UK; and the University of Würzburg, Germany.

DEMWEL utilized results produced in UPE. The latter ran from September 2001 to August 2004 and was carried out by researchers from the Central Bureau of Statistics, The Netherlands; the Central Bureau of Statistics, Norway; NIDI, The Netherlands; Statistics Finland; and the University of Joensuu, Finland.

Both DEMWEL and UPE were funded by the EU's Fifth Framework Programme. A grant from the Yrjö Jahnsson Foundation for editing this book is also gratefully acknowledged.