The authors present an example of a social constructivist framework and a backward design approach to enhance an underutilized peer mentoring program for teaching assistants. Following a needs assessment for quality improvement, the authors designed a mentoring workshop and revised guidelines: Mentoring pairs now use a four-step process to frame their efforts around synergistic objectives. Although program redesign was successful, as evidenced by increased participation, further improvements are informed by ongoing mentor feedback. The authors describe strategies and recommendations for developing or enhancing peer mentoring programs, and they provide materials that other departments can adapt to address context-specific needs.