A revised and improved translation of Pope Paul VI's encyclical letter, Humanae vitae. This encyclical address the important concern of the moral use of contraception in married life. It ultimately argues that the use of artificial contraception in marriage is immoral because it separates the unitive and procreative ends of marriage, both of which are necessary parts of God's plan for the institution and sacrament of Holy Matrimony. The year 2018 marks the 50th anniversary of the encyclical's publication, and its prophetic message is more timely than ever.