A study was conducted to determine if there were significant differences in vision between beginning readers who learn to read easily and those who learn with difficulty (dyslexics). In addition, the study examined the mean of the high achievers (rather than expert opinion) to discover the degree to which visual efficiency was normally needed for successful reading acquisition. Subjects were 144 students in the first and second grade classes in a Texas public school. Each child was individually tested at the end of the school year on 25 visual factors by an examiner who did not know the child's reading group placement. Results revealed significant differences in visual function between high and low reading achievers across grade, sex, age, and teacher effects. The mean scores of the high achievers were higher than those of the poor achievers on almost all measures, including binocular function (far-point vertical alignment, stereopsis, and fusion) and near-point visual acuity. Among the 19 first grade nonreaders, there were 18 cases of binocular problems and 17 cases of inadequate visual acuity--six times the number of visual problems found among the high achievers. The findings indicate that up to 95% of the reading disabled may be mislabeled, and that most of their difficulties could be prevented by a rigorous kindergarten or preschool visual screening and follow-up program. (FL)