The Code of Canon Law: A Text and Commentary, also commissioned by the Canon Law Society of America, was published in 1985. But much has changed in the nearly twenty years since the authors of the previous commentary did their work. The Church has changed. The Roman Catholic Church worldwide has come to terms with the 1983 Code of Canon Law, and has had considerable experience living by those new rules. It is that experience which this new commentary tries to capture and assess. Canon law has changed. The 1983 code itself has undergone just one formal amendment, however, many new documents and official interpretations have enlarged and reshaped the canonical scene in the intervening years. The Canon Law Society of America has done a new English translation of the code, published in 1999. This new translation, contained herein, forms the basis for the explanations and reflections that make up this new commentary. The authors have changed. Of the thirty-six contributors to this commentary, about three-quarters are different from the authors of the 1985 commentary.