The visual functions, before and after surgery, of 19 children with bilateral congenital cataract are evaluated. Some of the children, in spite of the poor vision before surgery and the late age at surgery, developed good vision with binocular functions. These children probably had an incomplete lens opacity in their early childhood which became completely opaque at an age at which irreversible stimulus deprivation amblyopia is unlikely to develop. Therefore, children over the age of 6 years with poor vision due to congenital cataract, on whom no information is available concerning the density of their lens opacities in early childhood, should not be regarded as having a poor visual prognosis.