Diabetic nephropathy is currently the most common cause of end-stage renal disease in the Western countries. Only approximately one third of patients with type 1 diabetes develop nephropathy; thus, because it is not feasible to aggressively treat all patients, it becomes very important to find early markers in order to identify patients at high nephropathy risk. To date the best available predictor of overt nephropathy is microalbuminuria. In this article we review the validity of microalbuminuria as a predictor of overt nephropathy and consider other markers of nephropathy risk.