The neurologically normal children affected by v.u. reflux frequently have miction disorders. The bladder-sphincter dysfunction can determine high intravesical pressures causing distortion of the vesico-ureteral junction in the same way of anastomotic obstruction. The urodynamic study allows the diagnosis of bladder-sphincter dysfunction and the careful therapeutic management. The medical treatment of the dysfunctional voiding may improve the evaluation of the reflux and reduce postoperatively complications and urinary tract infections. The Authors analyse their experience in the medical treatment of 40 children with vesico-ureteral reflux associated with miction disorders. The reflux resolved after medical treatment in 25% of cases and miction disorders in 50% of cases. The Authors stress the importance of careful diagnosis and treatment to improve results in this group of patients.