Miller Fisher Syndrome (MFS), which is characterized by ophthalmoplegia, ataxia and tendon areflexia, is generally considered as a clinical variant of Guillain-Barré Syndrome. However some features of the disease are still debated, particularly regarding possible central nervous system involvement. After presenting two new cases of MFS, the authors provide a critical review of the literature and discuss the nosographical position of the disease. The main conclusions can be summarized as follows: MFS is a predominantly axonal inflammatory neuropathy with prevailing involvement of oculomotor nerves. It is associated to spinal multi or polyneuropathy, which in mildly affected cases is manifested by areflexia, while in severe ones it can be responsible of sense and/or motor impairment. In addition to peripheral neuropathy CNS involvement, exclusive or more marked in posterior fossa, occurs not infrequently. The prognosis of the disease is often benign, but disabling or even fatal outcome is possible. Corticosteroid treatment, possibly because of antiinflammatory and/or immunosuppressive action, could be effective in some patients. Finally, in spite of some similarities with GBS, MFS should be considered as a separate entity with its own nosographical position.