The prevalence of vascular complications was assessed in 726 South Indian non-insulin dependent diabetes mellitus (NIDDM) patients with over 25 years' duration of diabetes. Retinopathy was detected in 52.0% of patients which included 41.7% with non-proliferative and 10.3% with proliferative diabetic retinopathy. Nephropathy was present in 12.7% and neuropathy in 69.8% of patients. While 32.8% of patients had ischaemic heart disease, the prevalence of peripheral vascular disease was only 15.4%. Multivariate logistic regression analyses showed that serum creatinine was associated with retinopathy, creatinine and post-prandial plasma glucose with nephropathy and post-prandial plasma glucose and age with neuropathy. This is one of the first reports on vascular complications in long-term diabetes from the Indian sub-continent.