Aim To determine whether there are inhomogeneities in arterial wall extensibility with age and hypertension. Background It has been known for some years that arteries lose their elasticity with increasing age and that they are less distensible in subjects with established and borderline hypertension than in age-matched controls. Results of data analysis In the carotid artery changes in arterial wall properties are not homogeneously distributed along the bifurcation. Both in older subjects and in those with borderline hypertension the loss of distensibility is most pronounced in the carotid artery bulb, while in borderline hypertensives the proximal part of the bulb, where the baroceptors are predominantly located, is more affected than other parts of the bulb. The loss of distensibility in the bulb may explain the diminished baroreceptor sensitivity observed in older subjects. The pronounced involvement of the proximal part of the bulb in the decreased distensibility in borderline hypertensives suggests that local stiffening, probably leading to disturbed baroreceptor sensitivity, may contribute to the development of hypertension in these patients. The pattern of inhomogeneities in wall distensibility in borderline hypertensives at a relatively young age (average 38 years) is similar to that seen in older normotensive subjects (average age 57 years), supporting the idea that arteries age faster in hypertensives than in normotensives. Conclusion In management of the borderline hypertensive patient, consideration should be given to preventing early ageing of the arterial wall rather than following arterial blood pressure.