Nearly ten years ago, practice recommendations supported use of the clinical classification of 'prehypertension' for people with systolic blood pressure of 120-139 mm Hg or diastolic pressure of 80-89 mm Hg. This recommendation was based on observations that these ranges of blood pressure were associated with enhanced cardiovascular and cerebrovascular risks compared with blood pressure less than 120/80 mm Hg. Recent observations, including the report by Yano and colleagues, also suggest that prehypertension is an important risk factor for the development of chronic kidney disease.