Higher education institutions often use mentoring to socialize faculty members into their academic disciplines and to retain them. Mentoring can also be used to change organizational culture to meet the needs of historically marginalized faculty members. In this article we focus on peer mentoring circles for women STEM faculty at a large, midwestern research university. Participants reported diverse, context-dependent mentoring needs and expressed interest in communicating issues raised in the circles to administrative leaders. A workshop for circle participants and administrators led subsequently to college-wide teams that addressed problems identified in the circles. We conclude that peer mentoring as a means to facilitate institutional change has great potential.