An association between alcohol consumption, blood pressure levels and the prevalence of hypertension has been described in close to twenty population studies. The relationship is independent of ethnic group, gender, type of alcohol, cigarette smoking and obesity, but additive to effects of obesity and oral contraceptive use. Several studies show a progressive rise in blood pressure throughout the entire range of alcohol consumption. Reports indicating a threshold for the effect at around 30 g ethanol per day (three standard drinks) may be artefactual due to underreporting of drinking levels. Drinkers consuming an average of 3 or more glasses per day have three to four times the prevalence of "hypertension" compared with teetotallers. A randomized, controlled trial of moderating alcohol consumption in normotensives has confirmed a direct pressor action of alcohol and is supported by studies in hypertensives. These observations have important implications for the prevention and management of essential hypertension in most communities.