In developmental glaucoma with trabeculodysgenesis (primary infantile glaucoma), goniotomy is a safe and highly successful operation and should be used in preference to trabeculotomy. Prognosis varies markedly with the age of onset of signs and symptoms. When present at birth or after the age of two years, the success rate is only about 30%. Between the ages of 1 and 24 months, success following one or two goniotomies is 94%. Eyes with successful goniotomies have now been followed for over 25 years with maintenance of pressure control without medication in most cases. The major complication has been amblyopia due to breaks in Descemet's membrane in the visual axis and to marked astigmatism and anisometropia. After 15 years, two cases developed an endothelial dystrophy and three had an IOP elevation. Obviously, periodic examination of such eyes will be necessary for life.