The purpose of this study was to devise a simple instrument that could be helpful in predicting reading success by classroom teachers and school administrators who are not experts in the field of reading. The subjects, 190 randomly selected first graders, were given "Alphabet" and "Numbers" of the Metropolitan Readiness Tests and "Information" and "Sentences" of the Wechsler Preschool and Primary Scale of Intelligence in the fall of 1969; in the spring of 1970 they took "Word Reading" and "Paragraph Meaning" of the Stanford Achievement Test, Primary Battery. A prediction equation was derived from the data on 96 of the children and then tested on the remaining group of 94. It was concluded that, when extreme scores are eliminated, a reading equation may be used to predict with approximately 85 percent accuracy which subjects will fall below a specific reading index or within a specified reading index range. Such a tool should not, however, be the sole basis for decision making, since such factors as social and emotional maturity, a child's readiness, and his mental age must be taken into account. (Author/MF)