The present study used a randomized control trial to examine the effects of a widely used multicomponent Tier 2-type intervention, Passport to Literacy, on the reading ability of 221 fourth graders who initially scored at or below the 30th percentile in reading comprehension. Intervention was provided by research staff to groups of 4-7 students for 30 min, 4 days a week throughout the school year (M = 90.45 lessons). Tier 1 instruction was observed to be of generally high quality and intervention fidelity was strong. Findings revealed small, average effects (ES = -0.14-0.28) in favor of intervention students on standardized measures of comprehension, but no effects on word reading or fluency measures. Exploratory analyses indicated that intervention effects may differ by students' comprehension abilities. Implications for intervention implementation and directions for future research are discussed.