A longitudinal study of 27 patients with infantile haemangiomas is reported. It confirmed the efficacy of local steroid injection as a method of treatment; 81.5% of patients showed a marked improvement, with the lesion reducing to 25% or less of its original size. Involution was most marked in the first two weeks but continued for up to four months after injection. Amblyopia was present in 43% of children and was usually the result of induced refractive error rather than obstruction of the visual axis or strabismus. Anisometropia was found in 68% of children, with a high incidence of asymmetric astigmatism on the side of the haemangioma. Following local steroid injection a marked reduction in astigmatism was noted in 53.8% of children, a lesser reduction in 15.4%, and no reduction in 30.8%. Successful treatment of the haemangioma, therefore, may not remove the risk of amblyopia, and regular refraction and visual assessment remain mandatory.