In recent decades there has been a seismic shift in world Christianity. Whereas formerly Christianity existed as a Caucasian Euro-American phenomenon, the majority of Christians today reside in the Southern Hemisphere, or the Global South. And what is true for the demographics of Christianity has followed lockstep for its theological developments. The era of German theologians setting the tone for global church are gone. Today, some of the loudest and most creative voices in theology speak from the emerging contingencies of the Global South, for example, promoting Latinx, Black, Caribbean, and Asian theologies and their influence often influences the conversation in the United States and Europe. In addition, just as the center of Christianity has moved geographically from north to south, so with theological seminaries in the west, which have declined as training centers for clergy. These events coincide with new theological centers are opening in Asia, Africa, Oceania, and Latin America. The bottom line is—contemporary Christianity today looks significantly different than it did a century ago, and publications have been slow to acknowledge, let alone describe and elaborate upon, this major shift to the largest religion in the world. These shifts guide our intentions in this book. Such a reference book, which could also be used as a textbook, therefore is very much needed. In fact, there is nothing like the contents of this single-volume book in the publishing market which allows for high-quality, interdisciplinary, and international dialogue.