Nine patients with chronic inflammatory demyelinating poliradiculoneuropathy (CIDP) were treated with intravenous immunoglobulin. All patients had been previously treated with prednisone and/or plasma exchange without effect. Objective improvement in clinical condition occurred in six patients. One patient became refractory after two treatment courses, two patients had no response. The results indicate that intravenous immunoglobulin has beneficial effects in a high percentage of patients with CIDP who are unresponsive to other treatments.