The Peer Assisted Learning (PAL) program at the University of Minnesota is a primary academic support program for historically difficult, introductory college courses that serve as gatekeepers to academic degree programs. This document is the training manual used for the new PAL facilitators that manage the small study groups. Based upon operating principles of other academic support programs and educational theories, PAL is integrated into the courses it serves. The PAL groups review essential course content, model cognitive learning strategies to deepen understanding, and promote metacognitive awareness so students are autonomous learners in courses without academic support services. The PAL approach operates at the confluence of collaborative learning, cooperative learning groups, and learning communities. This article provides a detailed overview of the PAL model, educational theories upon which it is based, and how variations of it are implemented at the institution. Quantitative and qualitative studies reveal academic and personal benefits for participating students and those serving as PAL facilitators. The studies validate the role of PAL with closing the achievement gap between students of different ethnicities and levels of academic preparedness for rigorous college courses in mathematics and science. Individual sections contain references and suggestions for further investigation. A bibliography of PAL-related publications is included.