We have come a long way in our understanding of the epidemiology, pathophysiology, and clinical significance of albuminuria in patients with NIDDM. However, substantial gaps remain to be defined. NIDDM nephropathy is a serious and increasingly burdensome disease for both the diabetic individual and the society at large. Onset of microalbuminuria, an early but common manifestation of NIDDM nephropathy, marks an ominous turn for the NIDDM patient, in whom its development forecasts a grave cardiovascular outcome. Interception of albuminuria with antihypertensive agents such as ACE inhibitors in otherwise healthy NIDDM subjects holds a significant promise but must first await further investigation.