Purpose of review: Dyslipidemia may contribute to the accelerated atherosclerosis of diabetes and the microvascular complications of nephropathy and retinopathy. In type 1 diabetes, the standard lipid profile is relatively normal, but lipoproteins may be abnormal in other aspects such as size, composition including nonenzymatic glycation and alterations in related enzymes, and function. These quantitative and qualitative alterations of lipoproteins may be influenced by both genetic and acquired factors. To provide the reader with an update of this ongoing area of research, we review the literature relevant to lipoprotein abnormalities in type 1 diabetes that was published between March 1, 2002 and February 28, 2003. Recent findings: A dyslipoproteinemia that resembles that usually associated with insulin resistance is revealed by lipoprotein subclass analysis by nuclear magnetic resonance. Further studies support there being abnormal composition and function of low-density lipoprotein and high-density lipoprotein in diabetes, such as nonenzymatic glycation and altered enzyme activities. New studies provide evidence linking some lipoprotein-related genotypes in type 1 diabetes to abnormal lipoproteins, and in some cases, to complication susceptibility. Summary: New tools, including novel assays and surrogate measures of vascular disease, have been used to increase knowledge of potential mediators of vascular damage and to suggest rational novel interventions to reduce the burden of the chronic vascular complications of type 1 diabetes. Further clinical and basic science research in the area is warranted to guide clinical practice.