Three children developed the congenital varicella syndrome following a maternal varicella infection during the second trimester of pregnancy. Systemic findings included a bulbar palsy, mild hemiparesis, cicatricial skin lesions, developmental delay, and learning difficulties. Ocular findings included chorioretinitis, atrophy and hypoplasia of the optic discs, a congenital cataract, and Horner's syndrome. Electroretinograms and pattern-reversal visual-evoked potentials recorded from the four eyes with chorioretinitis were attenuated and degraded. Two of the children had been misdiagnosed as having congenital toxoplasmosis. Chorioretinal scars probably occur more frequently with the congenital varicella syndrome than has been previously recognized and should be included in the differential diagnosis of congenital chorioretinal scars. Hypoplasia of the optic disc may develop after an intrauterine varicella infection during the 16th week of gestation. Children with the congenital varicella syndrome should be examined by an ophthalmologist to exclude ocular abnormalities. These abnormalities are often subtle and difficult to diagnose correctly.