Twenty-nine children with a single, unilateral cerebral infarct acquired pre- or perinatally were examined subsequently for an average of 43 months. No consistent pre- or perinatal events were identified to explain the occurrence of the stroke. The children acquired motor milestones at nearly expected times, even in the presence of hemiparesis. In children older than 2 years of age, I.Q. scores all were within the normal range. More than one-half of the children experienced seizures at some time during the follow-up period. Good intellectual and functional motor outcome can be expected in children with isolated perinatal stroke.