52 questions in three sections: Part 1 - God, Creation and Fall, Law; Part 2 - Christ, Redemption, Grace; Part 3-Spirit, Restoration, Growing in Grace.
I really love the format: question, answer, Scripture passage; then brief commentary provided by a historical source and a contemporary source.
Initially a project of Redeemer PCA in NYC, as a way of adapting questions and answers from Westminster Shorter & Larger Catechisms, Calvin's Geneva Catechism, and the Heidelberg Catechism. It has since been promoted by Crossway and The Gospel Coalition.
I am part of the Reformed, Presbyterian tradition. I heartily recommend the New City Catechism as a way of exploring the rich tapestry of Protestant/Reformed catechesis. This particular format is great for devotional reading and encourage reflection upon these beautiful and theological truths of Scripture.
I don't particularly recommend the New City Catechism as a substitute or replacement for your particular tradition's catechesis. Upon reading NCC, you will certainly appreciate the similarities among a wide spectrum of Protestant and historically Reformed groups (Anglicans, Reformed, Presbyterian, Baptist, etc), but at the same time it flattens some of the nuance and distinctions that do exist between us, especially regarding the sacraments. Of course, there are more aspects that I appreciate than I quibble.
The NCC is also great for someone who doesn't necessarily come from a tradition that promotes catechesis as an entry to one or more of the source catechisms.