The registry of the Network for Epidemiology and Information in Nephrology (Rein) was launched in 2002 to contribute to the development and evaluation of public health strategies aimed at improving the prevention and management of end-stage chronic kidney disease and to promote clinical and epidemiological research in this field. It relies on a network of nephrologists, epidemiologists, and representatives of patients and regulatory bodies, coordinated at the national and regional levels. In France, as of January 1, 2009, an estimated 68,000 people were receiving renal replacement therapy via dialysis or transplantation. The number of people who began renal replacement therapy in 2008 was approximately 9,300, or 147 people per million inhabitants per year. With a prevalence of 1,060 people treated per million inhabitants, end-stage chronic kidney disease—which carries a particularly high social and human cost—constitutes a major public health problem in France, as in most industrialized countries, requiring a dedicated information system to support epidemiology, public health, and quality of care. (R.A.)