This study will compare the effects, at comparable blood pressure control (systolic/diastolic <130/80 mmHg), of dual renin-angiotensin-system (RAS) blockade by half dose of benazepril and valsartan combination therapy as compared to single RAS blockade by benazepril or valsartan alone at full dose, 20 mg and 160 mg respectively, on ESRD and cardiovascular events in high-risk patients with type 2 diabetes and overt nephropathy, defined as serum creatinine >1.8 mg/dl and < 3.2 mg/dl and spot morning urine albumin to creatinine ratio >1000mg/g for the patients without previous ACE inhibitor and ARB therapy and >500mg/g for the patients with previous ACE inhibitor or ARB therapy and no specific contraindications to the study drugs. The relationships between renal and cardiovascular outcomes will also be evaluated.