CIDP is an autoimmune peripheral polyneuropathy. Clinical and electrophysiologic features indicate its heterogeneity, and such wide spectrum of the phenotype makes difficult to clarify complete pathogenesis. IVIg is an effective therapy no less than corticosteroids and plasmaphresis, and getting as the first choice for CIDP treatment due to the easy administration and less side effect. However, we have noticed that there is certain amount of non-responder, and this therapeutic heterogeneity could correspond to independent pathogenesis. In our previous report, axonal dysfunction, such as muscle atrophy and decreased CMAPs, is a significant factor to represent non-responder. Not only about therapy responsiveness, but aspect of long-term prognosis, subjects that show unfavorable prognosis indicate significant muscle atrophy and loss of myelinated fibres. Hence, decreased axonal function in peripheral nerve should critically affect CIDP pathogenesis. In practice, clinician should select proper treatment modality in light of clinical symptoms and appropriate medical costs, and if each one does not show enough efficacies, another should be admitted because responder for each modality is not necessarily overlapped. Although immunosuppressive agents might be admitted for non-responder to any other modalities, large randomized control trial is not done yet.