This study examined the effectiveness of a multisensory phonics-based reading remediation program for adolescent delinquents classified as poor readers living at a residential treatment center. We used a pretest--posttest control group design with random assignment. The treatment group participated in a 30-hr multisensory phonics reading intervention over a period of 8 weeks; the control group received standard reading instruction. Both groups completed pretest and posttest norm-referenced reading measures to assess changes in reading skills. The treatment group showed significantly greater improvement than the control group, with large effect sizes. Participants with higher preintervention reading scores and those with a higher verbal IQ responded more favorably to the reading intervention. We address the implications and limitations of this study.