The Institute on Religious Freedom held in North Aurora, Illinois, early this year, was an event of prime importance for an understanding of Vatican II's ""Declaration on Religious Freedom,"" the controversial document which Pope Paul himself recognized as ""one of the major texts"" of the Council. This book, edited and with a preface by the man who, perhaps more than any other, was responsible both for the formulation of the document and for its ultimate approval, is a collection of nine papers read at that conference by scholars Catholic and Protestant. Each paper treats of a different aspect of the over-all subject of religious freedom, but they all fall within the framework of four major topics: the basis of religious freedom in America, and the need for religious freedom. Father Murray's own introductory essay explains the evolution of the conciliar Declaration, and the document itself is reproduced in an appendix. The book is not for a general audience, since it presupposes at least a basic familiarity with philosophical and theological concepts, but it is a work for which there should be a widespread demand among both Catholic and Protestant theologians and it will be an indispensable addition to every theological library.