Using data from interviews with park rangers and volunteers, this chapter summarizes the impact of volunteersVolunteers, impact of in the National Park Service. The organizing framework for this summary and the chapters that follow is a Fence Model of Volunteer Impact. This model includes three levels of impact: ground/foundationalFence Model of Volunteer Impactfoundational/ground level, which focuses on benefits to the volunteer; functional/operational, which consists of impact for the organization, beneficiaries, and volunteerism as a practice; and, sky/societalFence Model of Volunteer Impactsocietal/sky level, which is centered on impact for democracy. The fence has two corner posts, which capture the essence of the NPS mission: to protect and connect parks from/to people, people from/to parks, and people from/to other people. The roles and functions of volunteers described in the seventh chapter are mapped onto the impact model. Volunteer and park ranger perceptions are compared and contrasted, suggesting areas of alignment and disconnection.