The purpose of this study was to examine the effect of a peer-mediated instructional approach on the teaching of phonological skills and reading comprehension for middle school (sixth- to eighth-grade) students with reading disabilities. All students (n = 38) were identified as having learning disabilities and reading at the third-grade level or below. One group was taught using a peer-mediated phonological skill program, "Linguistics Skills Training" (LST), and a peer-mediated reading comprehension program, "Peer Assisted Learning Strategies" (PALS). The contrast group was taught in the more traditional whole-class format using a widely implemented remedial reading program. The results showed significant differences between conditions, with students receiving the LST/PALS instruction outperforming the contrast group on Letter-Word Identification, Word Attack, and Passage Comprehension using the "Woodcock-Johnson Test of Achievement-III." Furthermore, large effect sizes for growth were found on Letter-Word Identification, Word Attack, and Passage Comprehension for the LST/PALS treatment group. No differences were found between conditions for reading fluency. Findings are discussed in regard to instruction delivery format (peer tutoring vs. whole class) with respect to best practices for middle school students with reading disabilities.