There is no single standard textbook that outlines the official Roman Catholic theological position in relation to other religions which then explicates this orientation theologically and phenomenologically in relation to the four main religions of the world and the flowering of new religious movements in the west. The present project will cover this serious gap in the literature. After outlining the teaching of Vatican II and the magisterium since then (chapter one), each subsequent chapter will be divided equally between (a) an exposition of the history and features of the religion or movement being studied; and (b) a serious theological analysis of these features, showing how these religions do have elements in common, as well as how they differ in fundamental ways from Catholicism.