Clinical data are presented of 63 artificially ventilated Guillain-Barré patients. About half of them had an antecedent event. In 57% the disease was heralded by sensory symptoms. The mean progressive phase lasted 12 days, the plateau 12 days and the recovery phase 568 days. In all patients one or more cranial nerves were involved, most often leading to facial palsy or difficulties in swallowing. Three-quarters of the patients had sensory signs, proprioceptive more often than superficial. Autonomic disturbances were common, especially hypertension and tachycardia. Twenty-two percent of the patients were severely confused in the first weeks of the disease. Laboratory examination showed atypical lymphocytes in the blood of 37% of patients and disturbed hepatic function tests in 79%. CSF protein level was elevated in all patients, with a mean value of 1.5 g/l.