RESEARCH PLAN: Over the past 4 years, we have collaborated with the DCCT/EDIC Study Group, and have made novel observations regarding vascular disease pathogenesis in Type 1 Diabetes. This work has focused our studies on specific pathogenic processes. We will now study a Type 2 Diabetes cohort from the VA Cooperative Study, "Glycemic Control and the Complications of Diabetes, Type 2", with high vascular disease event rates. These collaborations provide a unique opportunity to address the pathogenesis of accelerated atherogenesis in the two main types of diabetes, and will greatly augment the scientific knowledge that will be gained in the conduct of these world-class prospective trials.