Of the several books on celibacy I've ever read, this is the best one. It is written in Fr. Apostoli's gentle, non-intrusive style, and yet his arguments are so concise, so clear, so cogent, that the reader cannot fail to be impressed and persuaded. This will not cause everyone who thinks the Catholic Church is all wet on celibacy to change their mind, but for those it doesn't, they can no longer say after reading this book that the Church's teaching on this subject is arbitrary, stupid, or outdated.
Another great feature of this book is its treatment of pornography, homosexuality, and certain sexual practices (namely masturbation). In fact, it does a better job of explaining why the Church opposes these things than does the Catechism of the Catholic Church.
Bottom line: This is a great book for anyone who wants to be able to defend the Church or who doesn't understand why in the world the Church would make its priests and religious stay celibate. Especially good for those discerning a religious vocation.