Many observers greeted the Second Vatican Council (1962-65) as the most important religious event in the twentieth century. Its implementation and impact are still being felt in the Catholic Church, the wider Christian world, and beyond. One sea change that Vatican II brought concerned Roman Catholic attitudes towards Judaism, Islam, and other religions. Gerald O'Collins breaks fresh ground by examining in detail five documents from the Council which embodied a new mindset about other religious faiths and mandated changes that quickly led to international and national dialogues between the Catholic Church and the followers of non-Christian religions. The book also includes chapters on the insights that prepared the way for the rethinking expressed by Vatican II, and on the follow-up to the Council's teaching found in the work of Pope John Paul II and Jacques Dupuis. O'Collins ably illustrates how the Council made a startling advance in official Catholic teaching about followers of other living faiths. Carefully researched, the book is written in the clear, accessible style that readers of previous works by O'Collins will recognize.