Volunteering is central to any community-centered development intervention. As such, volunteers can contribute substantially to establishing and preserving peace. This paper describes various interpersonal, intergroup, and institutional theoretical perspectives to explain why volunteerism is particularly suited to peacemaking and peacekeeping. Special consideration is given to how involving young volunteers may be highly beneficial to peacemaking and peacekeeping. The paper emphasizes the “added value” of utilizing volunteers in peace and development organizations, and provides specific examples from the Eastern African region that illustrate how volunteerism is being used to prevent conflict, to mediate and transform active conflict, and to reduce the consequences of violent conflict.