The purpose of this study was to evaluate the effectiveness of a collaborative, multi-component reading intervention approach for adolescent students in high school with severe reading disabilities. Students in the experimental condition received 24 weeks of multi-component, differentiated small group interventions from a special-education teacher, a speech pathologist, and a paraprofessional with time to engage in cooperative groups and practice skills to mastery. Monthly progress monitoring informed the instructors of ongoing progress and drove instructional components based on student learning. The control group received whole classroom instruction combined with traditional, special educational supports. The results showed significant differences in growth between conditions on standardized measures of word reading fluency, oral reading fluency, and reading comprehension with medium effect sizes. No differences were noted in standardized vocabulary growth. Grade level progress in reading was not observed for either the experimental or the control groups; however, outcomes indicated only three “nonresponders” in the experimental group compared to six in the control. Findings are discussed in regard to practical application, limitations, and future research.