Assessment and treatment of varicose veins comprises a significant part of the surgical workload. In the UK, National Health Service waiting lists suggest that there is still considerable unmet need. This review analyses all published data on the epidemiology of varicose veins, paying particular regard to the differing epidemiological terminology, populations sampled, assessment methods and varicose vein definitions, which account for much of the variation in literature reports. Half of the adult population have minor stigmata of venous disease (women 50-55 per cent; men 40-50 per cent) but fewer than half of these will have visible varicose veins (women 20-25 per cent; men 10-15 per cent). The data suggest that female sex, increased age, pregnancy, geographical site and race are risk factors for varicose veins; there is no hard evidence that family history or occupation are factors. Obesity does not appear to carry any excess risk. Accurate prevalence data allow provision of appropriate resources or at least aid rational debate if demand is greater than the resources available.