The new Catechism of the Catholic Church, the first since the Council of Trent four centuries ago, will play a major part in shaping the consciousness of Roman Catholic Christians of the foreseeable future. Not only will it remain the foundational text for teaching Catholic doctrine for years to come, but it successfully consolidates the achievements of the Second Vatican Council, and presents the definitive modern synthesis of the Church’s ever-living Tradition. Aidan Nichol’s study introduces the reader to the doctrinal teaching of this massive text of almost three thousand clauses. Commenting on the vital first part of the Catechism section by section, he succeeds in highlighting its principal themes while drawing attention to the significance of the way they have been handled. More sympathetic to the intentions of the Catechism’s authors than some other recent commentators, Nichols is sensitive to the nuances of this magisterial text, and its immense theological import.