Pediatric multiple sclerosis has been increasingly recognized in the past 10 to 15 years; 3% to 5% of all multiple sclerosis patients experience their first attack in childhood. Childhood multiple sclerosis has a relapsing-remitting disease course. The first attack, or "acquired demyelinating syndrome," consists of optic neuritis, transverse myelitis, acute disseminated encephalomyelitis, and monofocal or polyfocal neurological deficits. The diagnosis of multiple sclerosis necessitates the clinical or magnetic resonance imaging confirmation of dissemination in space and time and exclusion of other disorders. The morbidity of childhood multiple sclerosis is significant; within the first 2 years from onset, 30% of children have significant cognitive impairment, 50% show signs of depression, and 75% are fatigued. The relapse rate in children with multiple sclerosis is higher than in adult-onset disease. Following acute treatment, recovery after the first attacks is usually excellent, but patients with childhood-onset multiple sclerosis reach permanent disability or enter the secondary progressive disease course 10 years younger than patients with adult-onset multiple sclerosis.