The relationships among pronunciation level (decoding), verbal level (listening), and accuracy level (reading) were investigated in grades 1 to 6, and for students who are in the advanced phase of decoding. The data collected were used to investigate the validity of the simple view of reading and the causal model of reading achievement which holds that pronunciation level (PL) and verbal level (VL) are the proximal causes of accuracy level (AL). A total of 135 students in grades 1–6 were given measures of nonword decoding, real word decoding, listening, and reading. All of the reliable variation in an indicant of the level of reading ability, AL, could be predicted from an indicant of the level of ability to decode real words, PL, and an indicant of listening level, VL. Furthermore, the strong relationship between pronunciation level, PL, and accuracy level, AL, did not evaporate for the students who had mastered basic decoding skills, as measured by nonword decoding tests. The correlations between pronunciation level, PL, and accuracy level, AL, were high even for students in grades 5 and 6, most of whom probably had progressed beyond the alphabetic phase (phonological recoding). Correlational support was found for the simple view of reading and the causal model which holds that AL is equal to the square root of the product of VL and PL. The above theory and supporting data were interpreted as suggesting that the level of reading accuracy, AL, of students can be improved the most throughout grades 1 to 6 by emphasizing instruction that will improve pronunciation level, or decoding, even for children who have progressed beyond the beginning to read phase which involves learning the alphabetic principal, or phonological recoding.