Christian Ethics at the Boundary is a splendid book! Karen V. Guth is rightly concerned that the divisions among those who identify with a particular approach to Christian ethics may create discord, which compromises our endeavors and forfeits our resources for addressing complex moral issues. Her focus in this book is the division between realist and witness approaches, represented here by Reinhold Niebuhr and John Howard Yoder. “What would Christian ethics look like,” she asks, “if we mobilized our differences for engagement rather than disengagement?” (5)
 It is important to note that Guth’s aim is not to reconcile the irreconcilable differences between witness and realist approaches. Rather, she seeks to “suggest opportunities for fruitful partnership and collaboration.” She contends that the differences between the two can be seen as “different sides of same coin.” Their different starting point – revelation (witness) versus experience (realist) – are, in the end, different ways to understand the relationship between revelation and experience. Their different attitudes toward engaging society – witness versus apology (realist) are different approaches to preventing cultural accommodation. And their differences in political strategies – pacifist identity and mission of the church (witness) versus participation in secular politics (realist) – are different ways to construe political responsibility. (37-8)
 Guth draws on Kathryn Tanner’s concept of Christian identity as constituted by “participation in a genuine community of argument” and her claim that the distinctiveness of a Christian way of life is formed “not so much … by the boundary as at it” to guide her own methodological approach. (22-23) Guth presents close, gracious readings of the public theologies of Reinhold Niebuhr, John Howard Yoder, and Martin Luther King, Jr., deepening our understanding of each. By engaging each with other approaches, she offers exceptionally constructive ecclesiological proposals that demonstrate “the substantive benefits of a methodological approach that privileges constructive engagement with difference.” (31) What makes her work especially valuable is her inclusion of feminist and womanist perspectives in this engagement.
 Guth remarks that “feminists may find it difficult to engage figures whose personal lives seem at odds with their own best insights.” Yoder’s persistent sexual violence against women “calls into question his commitment to feminism as part of and parcel of Christian mission.” Although King campaigned for civil rights, he did not address the evil of sexism, nor did he “treat women as equals in both his professional and personal life.” Although Niebuhr is not known to have behaved in demeaning ways toward women, “there is increasing evidence that [his] wife Ursula may have been the unacknowledged coauthor of much of his work, and that his privilege prevented him from acknowledging “the important work being done by black female contemporaries in Harlem.” Guth contends that “these discrepancies make engagement between these figures more, not less, valuable.” (21-22)
 In the chapter on Reinhold Niebuhr, “Churches as Self-Critical and Creative Cultures,” Guth begins with an examination of witness and feminist criticisms of him. She then adeptly develops his thinking on the nature and role of the church into a compelling, “Niebuhrian account of churches as self-critical cultures engaging in formative practices of contrition that cultivate the virtues of humility and hope, giving rise to creative ethical action.” (72) She describes this as “a witness – and feminist-inspired appropriation” of his thought. A significant observation is that Niebuhr goes a step further than witness approaches to consider not just “the distinctive calling of the church, but also its distinctive failing.” His attention to the “historical and social construction of the church as an institution provides a powerful tool,” Guth argues, “to address feminist concerns about church’s complicity in sexism” or charges that he failed to adequately account for women’s experience. With this approach, the “malformation effect” of violations of human dignity on church practices is not ignored. (104)
 The chapter on John Howard Yoder, “Feminism as Christian politics,” is surprising. Guth describes it as “a realist – and feminist-inspired appropriation” of Yoder’s pacifism. His claim that “Christian identity itself calls for feminist engagement” is the epigraph for the chapter. She observes that “analyzing Yoder’s relationship to feminism highlights surprising points of connection between his postliberal account and that of various feminist theologians.” (119) Of particular interest is her discussion of three core assumptions about the relationship of Christianity to the world shared by Yoder, some well-known witness theologians and certain feminists. She points out where Yoder differs from witness views and is closer to feminist ones: “Christianity is a culture with its own particular language, practices, and ethics; errors in the development of tradition require projects of retrieval; the church’s vocation is to provide countercultural witness of peace over against the world” (135-6) For Yoder, this witness includes “social egalitarianism” as an essential element. “His pacifism excludes neither politics nor gender justice. (146, 150)
 The chapter “Christian Ethics for the Creatively Maladjusted:” Martin Luther King, Jr.’s ’Feminist’ and ‘Womanist’ Politics of Love” is a vital part of this book. Guth addresses the critique of most womanists and feminists of King’s linking of agape with redemptive suffering, contending that “such views valorize suffering and condone the abuse of women.” She notes that womanist theologians Jacquelyn Grant, Joanne Marie Terrell, and Karen Baker-Fletcher recognize the constructive theological potential of this position. For example, Baker-Fletcher “clarifies that King does not affirm suffering per so, but voluntary suffering for a just cause.” (162-63) Guth argues that although King does not abandon understandings of agape as self-sacrifice, “he argues along the same lines as feminists in emphasizing the importance of self-love.” (169) King also upholds “the inherent dignity of human beings as persons who share in God’s creative power,” like womanists who draw on the imago Dei to affirm human beings’ creative capacities. (177) Guth argues that these views matter because they “emphasize the worldly nature of love as mutual, reciprocal, and community-creating” and disclose a “new vision of churches as communities of creativity.” (183)
 In the conclusion, “From the Genuine Community of Argument to the Beloved Community,” Guth contends that if the end is “beloved community,” then Christian ethicists should engage in a “genuine community of argument.”(190) In this book, she has shown that “doing Christian ethics at the boundaries models an approach to difference more in keeping with the beloved community and allows more creative, constructive responses to pressing moral problems.” (191) Here, she gives several useful examples. For instance, “engaging in self-critical and creative action enables the church to demonstrate solidarity – in the sense of complicity – with the rest of the world in wrongdoing, and to demonstrate solidarity – in the sense of commitment – to enact creative solutions to seemingly intractable problems.” She cites as an example Pope John Paul II’s 2000 Lenten prayer in Jerusalem, where he prayed for forgiveness for wrongs against other Christians and those of other religious traditions. (193)
 Some attention to ecumenical work would have been valuable, although perhaps it is beyond the scope of the book. Guth points to King’s observation of growing interest in ecumenical concerns as promising signs of unity, despite discord. (189) Of particular interest to the divide between realist and witness theologians is the World Council of Churches work during the Ecumenical Decade to Overcome Violence: Churches Seeking Reconciliation and Peace (2001-10). “An Ecumenical Call to Just Peace” was prepared by a drafting group with wide consultation, received by the Central Committee in February, 2011, and commended to the churches for study, reflection, collaboration and common action. The Preamble proclaims that “This call is a concerted Christian voice,” that “inspired by the example of Jesus of Nazareth … invites Christians to commit themselves to the Way of Just Peace.” It rightfully asserts that “Just Peace embodies a fundamental shift in ethical practice. It implies a different framework of analysis and criteria for action.” The Call “signals the shift and indicates some of the implications for the life and witness of the churches.”
 In Christian Ethics at the Boundary, Karen V. Guth makes crucial contributions to the field of Christian Ethics, particularly in terms of methodology but also her development of the public theologies of Niebuhr, Yoder, and King. This is an excellent resource for college, seminary and graduate libraries and courses in Christian Ethics, feminist and/or womanist ethics, and public theology. It should be of interest not only to Christian ethicists, but also for congregational study groups and anyone interested in the churches engagement in current ethical issues or the role of the church in public life.
 Guth’s work was inspired by King’s “Paul’s Letter to American Christians,” where King warns about the dangers of divisive denominationalism if “you are to be true witnesses for Christ.” (1)
 The DOV aimed to “engage the churches in initiatives for reconciliation that build on repentance, truth, justice, reparation and forgiveness,” “to create a culture of nonviolence,” as well as examine and develop “appropriate approaches to conflict transformation and just peacemaking in the new globalized context.”
 “An Ecumenical Call to Just Peace,” emphasis added. The “Call” and other resources on the Decade are available at http://overcomingviolence.org/en/resources-dov/wcc-resources.html. The work of Glen Stassen and colleagues who developed the Just Peacemaking paradigm is also relevant here. See Just Peacemaking: The New Paradigm for the Ethics of Peace and War, ed. Glen H. Stassen, The Pilgrim Press, 2008, previously published as Just Peacemaking: Ten Practices for Abolishing War, 1998, 2004, and Interfaith Just Peacemaking: Jewish, Christian and Muslim Perspectives on the New Paradigm of Peace and War, ed. Susan Brooks Thistlethwaite, Palgrave Macmillan, 2012.