This paper contends that there is a range of converging evidence that beginning readers use the implicit lexicalized form of phonological recoding, as claimed by the knowledge sources theory. To reinforce the contention, the paper first discusses the alphabetic principle and theories of beginning reading and then considers lexicalized phonological recoding in the knowledge sources theory. It then questions whether there is empirical research evidence about this claim of the knowledge sources theory and answers by citing findings from several studies of beginning readers which support the theory. The paper concludes that the knowledge sources theory explains how beginning readers can progress in very diverse instructional environments and that the knowledge sources theory provides an expanded view of children's acquisition and use of the alphabetic principle. Contains 15 references. (NKA)