Forced-choice preferential-looking acuity estimates from cortically visually impaired (CVI) infants and children were compared with three measures of visual function. Mean acuity deficit varied with fixation, tracking and visual impairment. Acuity deficit correlated with centile score for sensorimotor skills, but not for gross motor skills. The results suggest that these estimates provide information about the CVI child's ability to use vision in everyday life. Correlations were found between initial acuity deficits and acuity deficits measured from three months to six years later. Forced-choice preferential-looking acuity estimates may be useful for evaluating treatment response and establishing guidelines for educational materials for these infants and children.