As the Catechism of the Catholic Church is one of the most sublime documents produced by the modern church, I use it religiously; but, as there are two editions, which one I use as the primary source has required quite a bit of thought on my part.

The first edition of the Catechism of the Catholic Church, published in 1994 was somewhat different than the second edition published in 1997, especially regarding the use of capital punishment—a key issue for our apostolate, The Lampstand Foundation.

Pope John Paul II’s official biographer, George Weigel, (1999) wrote regarding the change from the first edition to the second in relation to John Paul’s 1995 encyclical Evangelium Vitae.

“The Catechism was subsequently revised in its definitive Latin edition to cohere with the encyclical’s teaching, which seemed to reflect Karol Wojtyla’s experience of, and loathing for, the state’s power of execution.” (p. 758) Weigel, G. (1999). Witness to hope: The biography of Pope John Paul II. New York: HarperCollins Publishers.

After much consideration I’ve come down on using the first edition as the authoritative Catechism of the Catholic Church http://www.amazon.com/Catechism-Catholic-English-Liguori-Publications/dp/0892435666/ref=pd_sim_b_1?ie=UTF8&refRID=098V0W3QX38SHZYMQ4M0
because it was produced with input from all the bishops of the world vesting it with a deeper authority than the second, in my opinion, but I still use the second as the secondary resource.

Weigel comments further:

“The Catechism went through nine drafts, all of which were first prepared in French. Bishops around the world were consulted throughout the drafting process, and the editorial committee’s work was continually reviewed by the oversight commission [chaired by Cardinal Joseph Ratzinger, now Pope Benedict XVI] John Paul followed the work closely, according to Schonborn, but rarely gave direct comments on the draft. One exception, widely noted, was the catechism’s discussion of the morality of capital punishment… “(Ibid. p. 661)

The first edition was also published with two wonderful companion volumes:

The Companion to the Catechism of the Catholic Church: A Compendium of Texts Referred to in the Catechism of the Catholic Church: http://www.amazon.com/Companion-Catechism-Catholic-Church-Compendium/dp/0898704510/ref=sr_1_1?s=books&ie=UTF8&qid=1400953737&sr=1-1&keywords=the+companion+to+the+catechism+of+the+catholic+church

Introduction to the Catechism of the Catholic Church http://www.amazon.com/Introduction-Catechism-Catholic-Christoph-Schonborn/dp/0898704855/ref=sr_1_1?s=books&ie=UTF8&qid=1400953796&sr=1-1&keywords=introduction+to+the+catechism+of+the+catholic+church