Most children who develop renal damage (scarring) after urinary-tract infection have vesicoureteral reflux. Voiding cystourethrography is therefore usually recommended as the initial radiologic study in children with urinary-tract infection. However, renal damage may occur also in the absence of reflux. The aim of this investigation was to determine the sensitivity and predictive value of reflux during voiding cystourethrography in identifying children at risk for renal damage. Eighty-four consecutive children, 2 months to 6 years old, with nonobstructive, first-known, febrile urinary-tract infection underwent voiding cystourethrography and urography. Twenty-seven (32%) had reflux and 10 (12%) had or developed renal damage. Two of the children and four of the kidneys with renal damage had no reflux at initial examination. The sensitivity of reflux as a marker for renal damage was 80%, specificity was 74%, positive predictive value was 30%, and negative predictive value was 96%. Thus, most children who develop renal damage after urinary-tract infection have reflux during voiding cystourethrography. However, there is a risk, albeit small, for renal damage to occur in the absence of reflux.