Both increased synthesis and decreased catabolism of lipoproteins may account for the severe hyperlipidemia which frequently occurs in patients with the nephrotic syndrome (NS). Nevertheless the complex relation between hyperlipidemia and proteinuria remains unclear and still debated. Increased levels of serum total cholesterol, of low-density lipoprotein and of apolipoprotein B are the most characteristic reported abnormalities placing these patients at high risks for atherosclerotic vascular disease. Moreover recent experiments have suggested that hyperlipidemia may also play a role in the progression of renal disease. Thus the reasons for using hypolipemic treatment are now growing in number and recent trials with lipid lowering medication have been successful without major side effects.