Renal scarring associated with vesico-ureteric reflux (VUR), most commonly detected in young children, is associated with a significant risk of developing hypertension in later life. Hypertension in reflux nephropathy contributes significantly to morbidity including deterioration of renal function. The mechanism of onset of hypertension is not clear although abnormalities of the renin-angiotensin system and sodium/potassium ATPase activity have been described in some cases. It is becoming clear that radiologically detectable renal scars or small kidneys may histologically indicate a variety of diagnoses. Prediction of the risk of developing hypertension in individual cases is difficult and therefore regular follow-up remains the only current means of recognising these subjects. Although prevention of renal scar development in children with VUR may offer some benefit in reducing the incidence of hypertension, there is no uniform action that can definitely achieve this, particularly in the very young, before any urinary infection occurs. Primary VUR seems to be a disorder with mendelian dominant inheritance and location of the gene may offer some hope of early identification within certain families. Timely introduction of preventative measures may then be possible even though reservations exist about their effectiveness.