Dyslipoproteinemia in non-insulin-dependent diabetes mellitus (NIDDM) is an important risk factor in the development of atherosclerosis and glomerulosclerosis. The lipid profile of NIDDM patients is characterized by elevated serum triglycerides and VLDL levels and reduced HDL cholesterol levels. Serum LDL levels may be elevated as well in some patients with NIDDM, but several alterations in the biochemical and physical properties of LDL particles are more characteristic resulting in reduced receptor specific uptake of these lipoproteins. Non-enzymatic glycosylation of LDL and augmented oxidation is common in diabetic patients making lipoproteins susceptible for uptake by the macrophage scavenger receptors and thus leading to foam cell formation and further glomerular damage. A reduction in the progression of diabetic nephropathy by lowering proteinuria and thereby serum cholesterol during treatment with ACE-inhibitors demonstrates the importance of such a therapy. The multiple factors involved in the pathogenesis of diabetic nephropathy are difficult to evaluate in regard to their individual contribution. Nevertheless antiproteinuric and lipid lowering therapy can be expected to reduce vascular damage and the progression of diabetic nephropathy.