The "Epidemiology and Information Network in Nephrology" (Rein) was established to address public health issues raised by treatments for end-stage chronic kidney disease. Its purpose is to contribute to the development and evaluation of health strategies aimed at improving the management of kidney disease in its various dimensions: healthcare organization and clinical practices. This objective requires a better understanding of health needs, the availability of care, and patient outcomes. Rein is part of an evidence-based approach to medicine and public health policy consistent with Decrees No. 2002-1197 and 2002-1198, which establish a new dialysis regulation system based on population needs, and with the Public Health Policy Act of August 9, 2004, which sets explicit objectives for chronic kidney disease. Following a pilot phase that demonstrated the project’s feasibility, Rein is now operational in 13 regions representing 70% of the French population. This article describes these objectives, the methods, the technologies, and the expected results. (Introduction)