This volume differs from many quincentennial discussions of the Protestant Reformation—and ecumenical scholarship more generally—in that it shifts the focus from Europe and the West to the global South, where ecumenism's promises and challenges are quite different. In postcolonial and post-missionary Africa, the churches continue to expand, competition among denominations is lively, and Christian rivalry with Islam is often a reality. In Latin America, Protestants have severely eroded the Catholic Church's hegemony, originally forged in the zeal of the Counter-Reformation to combat the perceived errors of Luther and Calvin. In India, the Christian churches are a tiny, beleaguered minority facing an increasingly militant Hindu nationalism. These essays pay close attention to the different contexts of intra-Christian relationships worldwide—the actual situation on the ground. If ecumenism will succeed, it cannot be simply a matter of experts at a conference attempting to agree about doctrines abstracted from the contexts in which they were forged, the contexts in which doctrinal disagreements caused ecclesial ruptures, or the contexts in which Christians continue to live out our divided existence. This volume attempts to be sensitive to the lived experience of divided Christians in whatever part of the world they find themselves.