The purpose of this book is to develop a new way of thinking about religion in the emerging space age. Anyone who desires to make a serious study of religion should recognize that we are challenged by two imperatives. The first, religious pluralism, challenges us to take seriously the religious significance of all of the major religions. We must learn to listen with respect and open minds as we evaluate their religious insights. The second challenge stems from a new scientific world view and the rapidly developing technology that characterizes space age culture. Our recently acquired ability to venture off our home planet and travel to other worlds, coupled with speculation about extraterrestrial intelligence, constitutes this second challenge that we will call the "extraterrestrial imperative." The central theme developed in this book is that in responding to these two challenges, we will be sketching the outline of an ecumenical religion that reflects global and extraterrestrial thinking. We might call it "space age theology" since we will be identifying the basic principles that will give shape to an emerging cosmic religion.