Perhaps the most nebulous statement promulgated by Vatican II was that concerning religious freedom (the ""Declaration of Religious Freedom""); and, unfortunately, subsequent ""clarifications"" have done little to dispel the doubts confusions, and fears of Catholics on this matter. It is ironic that it has been left for Dr. Carrillo de Albornoz, a Protestant, of the World Council of Churches, to produce the first straightforward, unambiguous and truly lucid explanation of the implications of that controversial document. He first explains what religious freedom means, then establishes the necessity and rationale for it from both reason and revelation. A final section is devoted to the clarification of some particularly thorny doubts and to a prognosis of the future of religious freedom particularly as a factor in ecumenism. This book is of truly contemporary interest, a ""must"" for anyone interested in the theory and practice of a basic, albeit belatedly recognized, human freedom.