Inherited kidney diseases are frequently encountered in adults; the diagnosis is often made and they usually progress to renal failure at this age. Autosomal dominant polycystic kidney disease is the most prevalent. It is one of the most common inherited diseases, involving 1 in 400 to 1,000 individuals. Renal cysts growth is responsible for hypertension and renal failure; polycystic kidney disease represents 6 to 7% of the causes of end-stage renal failure in adults. The disease also encompasses extra-renal localisations, i.e. liver cysts and intra-cranial aneurysms. Multiple renal cysts may be found in other inherited disorders, such as tuberons sclerosis and von Hippel-Lindau disease. Alport syndrome is the second most prevalent inherited kidney disease, characterized by various abnormalities of type IV collagen molecules. Molecular diagnosis is possible in some families, which makes genetic counselling more reliable. Finally renal involvement is frequent in a great variety of inherited metabolic (Fabry's disease, glycogen storage disease type 1, hyperuricemic nephropathy) or non-metabolic (nail-patella or Bardet-Biedl syndrome) diseases.