Boys must have been between 6 and 12 years of age; girls between 6 and 11 years of age. All children must have had at least 0.5 diopters of myopia in both eyes, near-point esophoria, at least 20/25 acuity in each eye, and 40 seconds of stereopsis and must have been free of ocular disease or systemic disease that may have altered refraction. All subjects were willing to wear bifocal spectacle lenses for 30 months.