In South Africa, in urban but not rural areas, hypertension is far more common in Black than in White adults. To throw light on this adverse situation, blood pressures are being determined in various segments of Black populations, in the present instance on series of school pupils aged 16 to 17 years, in rural and urban areas. Mean data lay within the ranges of means published for Black children in the USA and for White children in the USA and elsewhere. Neither level of salt nor of sugar intake appeared influential; the same applied to obesity. Evidently, the noxious factors which promote the excessively high frequencies of hypertension in urban Black adults are not yet in operation in young adolescents.