There are many mechanisms underlying the hypertension which occurs after thoracic transplantation. Previous disease, effects of cyclosporin, tacrolimus and steroid immunosuppression and cardiac denervation are major contributory factors. Abnormal sodium and water balance is an important common mediating factor. A new approach is clearly needed for classifying the severity of hypertension in these patients taking into account day-night variation and total blood pressure (BP) load. This would allow improved strategies for investigation and treatment. The evidence suggests that ambulatory BP measurements should be included in the assessment of initial severity of post-transplant hypertension as well as response to treatment. Further studies are needed to look at the effects of raised clinic and 24-h ambulatory BP and its treatment on longer term morbidity and mortality in thoracic transplant patients.