Antihypertensive drugs have an important role in the treatment of malignant hypertension, secondary prevention of cardiovascular disease, and primary prevention for people at high risk: those with moderate to severe hypertension (≥160/100 mm Hg), diabetes, or chronic kidney disease. Debate continues, however, about the level at which treatment should begin and the appropriate targets for treatment. The greatest uncertainty surrounds mild hypertension (140-159/90-99 mm Hg), which accounts for over 60% of those with hypertension or 22% of the global adult population. Evidence suggests no net benefit from drug treatment of mild hypertension in people without the higher risks of diabetes or chronic kidney disease. Nevertheless, most people with mild hypertension are treated with drugs. In this article, we examine the overdiagnosis and overtreatment of mild hypertension.