End-stage renal failure affects more than 50000 people in France, or nearly 1 per thousand; 60% receive dialysis and 40% have a functioning transplanted kidney. Its incidence is stable, except among those older than 75 years, in whom incidence continues to rise. In nearly half of all cases end-stage renal failure follows hypertension or diabetes, principally type 2 noninsulin-dependent diabetes. About 30% of patients begin dialysis on an emergency basis; this demonstrates the elevated frequency of inadequate predialysis management of chronic kidney disease, from any cause. Since 2002, "chronic kidney disease" has been defined as the persistence for more than 3 months of kidney damage, which is either a laboratory or histologic or morphologic abnormality or a glomerular filtration rate (GFR)<60 mL/min for 1.73 m(2) of body surface, independently of the initial cause. It is classified by stage of severity to facilitate the application of good clinical practice guidelines. Moderate or severe chronic kidney disease, defined by GFR<60 mL/min/1.73 m(2) is approximately 40 times more common than end-stage renal failure. Individuals with chronic kidney disease are much more likely to die of another disease than to progress towards with end-stage renal failure. Diabetes, hypertension, a history of cardiovascular disease, nephrectomy, recurrent urinary infections or kidney failure in the family are all factors that should result in regular check-ups for chronic kidney disease. In two thirds of those older than 70 years, the GFR estimated by laboratories according to Cockcroft and Gault's formula is between 30 and 60 mL/min, but this does not always signal the presence of chronic kidney disease.