This paper reviews research evaluating the effectiveness of Peer-Assisted Learning Strategies (PALS) for reading. Nearly fifteen years of research has demonstrated the effectiveness of this classwide peer tutoring program in improving the reading performance of high-, average-, and low-performing students, including students with disabilities, from kindergarten through high school. PALS activities and procedures for grades two through six, high school, kindergarten, and first grade are reviewed, as well as research indicating its effectiveness and feasibility for classroom implementation. Research exploring student unresponsiveness to PALS is also reviewed. The implications and recommendations for practice are discussed. For more information about PALS research, training workshops, and access to materials, visit the PALS website at http://www.peerassistedlearningstrategies.net.