Dyslipidemia is commonly observed in nephrotic syndrome, in chronic renal failure, and after renal transplantation. The patterns of dyslipidemia, however, differ among these three conditions, and the origins and mechanisms responsible for abnormalities in lipoprotein metabolism in each are not well understood. Whether these dyslipidemias contribute to the development of atherosclerosis and coronary heart disease is uncertain, but it is probable that they do. Important questions are whether an attempt should be made to treat the various renal dyslipidemias, and if so, by what means. Also of current interest are dyslipidemias in the nephrotic syndrome, chronic renal failure (uremia), and the post-renal transplantation state.