This article reports on a 4-year longitudinal study of the effects of Literacy Collaborative (LC), a school-wide reform model that relies primarily on the one-on-one coaching of teachers as a lever for improving student literacy learning. Kindergarten through second-grade students in 17 schools were assessed twice annually with DIBELS and Terra Nova. Scores from the study's first year, before coaching began, offered a baseline for assessing the value added to student learning over the following 3 years. A hierarchical, crossed-level, value-added-effects model compared student literacy learning over 3 years of LC program implementation against observed growth under baseline conditions. Results demonstrated increasing improvements in student literacy learning during LC implementation (standard effect sizes of .22, .37, and .43 in years 1, 2, and 3, respectively), and the benefits persisted through subsequent summers. Findings warrant a claim of substantial effects on student learning for the LC coaching model.