Craniosynostosis, the premature fusion of one or multiple cranial sutures, can be complicated by visual failure resulting from raised intracranial pressure (ICP). Of the 290 children operated on at the Birmingham Children's Hospital between 1978 and 1995 for craniosynostosis, 9 were found to have defective visual acuity attributable to raised ICP. Mean age at presentation was 3.11 years (range: 1-6 years) and mean follow-up, 7.33 years (range: 1.5-16 years). All these patients presented significantly later than usual, and 5 of them developed recurrent craniosynostosis. At the initial examination bilateral papilloedema was seen in 4 patients, unilateral disc oedema in 1 patient, bilateral optic atrophy in 3 patients and unilateral optic atrophy in 1 patient. Following decompressive craniofacial surgery, the visual outcome was good in 4 out of 5 patients with papilloedema and poor in all patients with optic atrophy. visual failure resulting from raised ICP in craniosynostosis is a devastating complication, which appears to be associated with late presentation and recurrent craniosynostosis.