We studied and treated prospectively 62 neurologically normal children with vesicoureteral reflux using urodynamic techniques to identify uninhibited bladder contractions with voluntary sphincteric obstruction (dyssynergia). All children received antibiotic prophylaxis. Anticholinergic drugs were used additionally to treat uninhibited bladder contractions. During 6 years of followup treatment of uninhibited contractions produced a 4-fold reduction in the incidence of recurrent urinary infection and tripled the rate of reflux resolution compared to controls. These data suggest that uninhibited contractions with voluntary sphincter obstruction are an important prognostic finding in children with reflux, which when treated successfully can alter the disease course and may make surgical therapy of reflux unnecessary for some.