Does God have a sex plan? By that is meant, did God design the human race to function best by following a specific plan for how human beings are to interact sexually and to reproduce? What happens when this plan is followed, and when it is not followed? Are different varieties of sexual behaviors just as legitimate as God's original sex plan? This two-volume set explores these controversial questions. Many issues are discussed that are related to sex, including but not limited to: monogamy, marital sex, polygamy, incest, homo-sexuality, premarital sex (fornication), extramarital sex (adultery), celibacy, transsexualism, reproduction, infertility, contraception, abortion, sexual harassment and assault, masturbation, pornography, and gender roles. The bulk of this set consists of looking at relevant Scripture passages, studying them more or less in Biblical order, starting with the Book of Genesis, then moving on through to the Book of The Revelation. The verses are quoted then commented upon, with the focus on what the passage is teaching and the implications thereof. Along the way, extra-Biblical arguments for and against the Biblical position are addressed. Shorter such discussions are indicated in the text as being a "side note," while longer discussions are separated by the subtitle "Extra-Biblical Discussion." But the focus is on the Scriptures. The addressed issues are often controversial, provoking strong emotions and heated arguments. But they are dealt with in as a congenial manner as possible. However, no attempt is made to be PC ("politically correct"). Instead, fidelity to the Scriptures is the goal. This exposition of the Scriptures is not meant to offend, but if someone is offended, it is because they are offended by the Scriptures or sound reasoning, not by this writer's opinion. It is this writer's hope and prayer that this set will be received by both Christians and non-Christians as an honest attempt to understand what the Bible has to say on these topics and the implications thereof, while also considering relevant extra-Biblical arguments and material.