The movement of people spatially at an unprecedented scale is a special social phenomenon of the 21st century. Among these people on the move are those who take up residence away from their place of origin-the "diaspora"-who are the focus of this study. This book is an interdisciplinary study on the 21st century demographic reality that led to the development of "diaspora missiology" as a new missiological paradigm, and the need to practice "diaspora missions" as a new mission strategy.