The Religious Society of Friends (Quakers), have a long history of involvement as unofficial third party conciliators in world conflicts. Speaking truth to power, they walk the delicate line between advocating for the disempowered whilst building relationships with the adversary. Considerable scholarly ambivalence exists regarding religion's dual agency in contributing both to violence and to peace. While a large number of studies on religion and violent conflict have been undertaken and the realities of religious extremism are well recognized, the good done by faith-based actors is not so well researched. This study responds to the call for empirical in-depth evaluation of religious peacebuilding practice. It explores peacebuilding approaches in two Quaker reconciliation initiatives in the Pacific region from a sustainable Peace Studies perspective.Eight in-depth 70 minute interviews with four interviewees (two from Australia and two from Aotearoa New Zealand) were conducted and 22 Yearly Meeting Epistles were also examined. This data was analysed by using a responsive interviewing formal coding model and a grounded theory model. Resulting themes were then examined from Lederach's transformational perspective of conflict, which argues that constructive change must occur across four dimensions—personal, relational, structural and cultural—for peace to be sustainable.The over-arching theme that emerged from this study on Quaker peacebuilding was a transformative approach to peacebuilding that fitted strongly with the sustainable peacebuilding literature. In contrast to the traditional western-centric peacebuilding paradigm, the four Quakers' approaches to peacebuilding put social reconstruction to the fore, embracing universal humanitarian ideals. These findings illustrate the peacebuilding processes of a lesser-known non-proselytizing religious movement—the Quakers—whose tradition is rooted in personal, social and political transformation. This study contributes to the mounting body of evidence that religious actors, given certain constraints, have potential to contribute towards the constructive and peaceful resolution of conflict.