The burden of erectile dysfunction has not been well documented across age and ethnicity. A number of studies have reported a prevalence of around 35% in middle-aged men, rising to over 75% in elderly men. Some ethnic groups appear to be at increased risk. Much higher rates have been reported in men with diabetes – up to 90%. In this article, Ronald Ma and Peter Tong describe the mechanisms linking erectile dysfunction and diabetes, its association with atherosclerosis, and look at the cardiovascular implications for men with diabetes and erectile dysfunction.