Clinical features in a comparably studied group of hypertensive and normotensive adolescents are described. Hypertensive hyperreninemia occurred in four of 28 hypertensive adolescents; suppressed plasma renin activity was found in five of 27 hypertensive adolescents. Only one of five adolescents identified as having suppressed plasma renin activity after ingesting a low-salt diet for three days had a hyporesponsive response to acute extracellular volume contraction. Pressure natriuresis was documented in six of 32 adolescents. Compared to normotensive, the hypertensive group was found to have elevated levels of serum uric acid. Plasma renin activity was higher in hypertensive children with hyperuricemia than in those with normouricemia. The hypertensive adolescents also had higher levels of serum calcium and phosphorus. Two-thirds of the hypertensive adolescents had echocardiographic changes of myocardial hypertrophy. No ophthalmologic nor renal abnormalities were documented in the hypertensive group. A review of factors influencing blood pressure changes during childhood and current considerations for therapy are included.