We have studied kidney growth and function in 38 patients with either unilateral (23) or bilateral (15) vesicoureteral reflux (VUR) and reflux nephropathy (RN). Average follow-up was 38 (range 12-84) months. Surgery was performed in 93.3% of units. Renal length measurement alone was not satisfactory for detection of focal scarring, whereas cortico-renal index was much more discriminant. Growth of kidneys with bilateral RN was impaired, but there were no correlations with either VUR grade not with urinary infection relapses after VUR cure. Growth was also impaired in unilaterally scarred kidneys and renal length measurement revealed itself as very unsatisfactory in them. Contralateral unscarred kidneys underwent hypertrophy in some cases and growth patterns suggested that hypertrophy will become more evident as follow-up goes on. Neither glomerular filtration rate nor fractionated Na excretion were useful to detect renal lesions, whereas concentration capacity revealed renal damage in bilateral cases. There was hypertension in only one child, but peripheral blood renin was elevated in 15.62% of patients.