Eleven children with acute inflammatory polyneuropathy were treated with a short course of intensive plasmapheresis. The 5 males and 6 females ranged in age from 19 months to 16 years (mean: 7.8 years). The interval from disease onset to the initiation of plasmapheresis therapy was less than 7 days in 5 patients and less than 2 weeks in the others. At the time of the first plasmapheresis, 3 patients were on respirators (Grade 5 on the Guillain-Barré syndrome scale 0-6); 7 were bedridden (Grade 4); and 1 required assisted ambulation (Grade 3). One week after the last plasmapheresis, all but 1 patient had improved by 1 or more grades on the Guillain-Barré syndrome scale. At subsequent examination 6 months later, all patients were ambulatory and 9 of 11 had no significant neurologic findings. Electrophysiologic studies performed shortly before treatment initiation revealed predominant demyelinating neuropathy in 9 and axonal changes in 2. During the 76 plasmapheresis procedures, no severe complications were encountered. Although the number of patients treated is small, the clinical response observed would indicate plasmapheresis to be a safe and effective therapy in children with acute inflammatory polyneuropathy.