Chronic venous disease of the legs occurs commonly in the general population in the Western world. Estimates of the prevalence of varicose veins vary widely from 2–56% in men and from 1–60% in women. These variations reflect differences in variability of study populations including age, race and gender, methods of measurement and disease definition. Definitions of chronic venous disease may rely on reports of varicose veins by study participants, based on self-diagnosis or recall of a diagnosis, or on a standardized physical examination. Venous ulceration is less common, affecting approximately 0.3% of the adult population. Age and pregnancy have been established as risk factors for developing varicose veins. Evidence on other risk factors for venous disease is inconclusive. Prolonged standing has been proposed, but results of studies should be interpreted with caution given the difficulty in measuring levels of posture. Obesity has been suggested as a risk factor in women, but appears to be an aggravating factor rather than a primary cause. Other postulated risk factors include dietary intake and smoking, but evidence is lacking. Longitudinal studies using standardized methods of evaluation are required before the true incidence of chronic venous disease and associated risk factors can be determined.