Percutaneous transluminal renal angioplasty (PTRA) was performed in 12 children and adolescents with renal artery stenosis. Patients were divided into three groups: those with a short stenosis in the middle or distal part of the renal artery (n = 5), those with a short stenosis at or near the origin of the renal artery (n = 3), and those with a long stenosis at or near the origin (n = 4). The patients in the first group responded to PTRA. Those in the second group had a poor clinical response, and dilation was unsuccessful in the patients in the third group, who remained hypertensive. The location and length of the renal artery stenosis and its underlying cause appear to be important in determining the results of PTRA.