Rather than end the debate over artificial means of contraception once and for all, the encyclical letter ''Humanae Vitae'' only energized the debate when it appeared in 1968, and that debate continues to this day. Janet E. Smith presents a comprehensive review of this issue from a philosophical and theological perspective. Tracing the emergence of the debate from the mid-1960s and reviewing the documents from the Special Papal Commission established to advise Pope Paul V1, Smith also examines the Catholic Church's position on marriage, which provides the context for its condemnation of contraception. Smith analyzes the various moral principles that are crucial to an understanding of ''Humanae Vitae''. She offers new renderings of several traditional arguments based on natural law, among which is an argument based on personalist values. Throughout the book, Smith's observations and perceptions contribute to a thought-provoking study.