Research findings concerned with the relationship between the child's oral language behavior and learning to read are described. A cognitive-biological approach to the child's perceptual system development is taken, and data are presented to support both the developmental point of view of language development and the point of view that the child reconstructs all sensory input. Two critical phases in learning to read are delineated: (1) the child's previous ability to comprehend and decode speech auditorily as a prerequisite to decoding print and (2) the child's understanding of the relationship of spoken speech to the written symbol system for speech. The point is made that oral language is important only in that it may reflect cognitive and perceptual mastery of language, but it is an insufficient and inaccurate predictor of many children's capacity to learn how to read. A bibliography is included. (CM)