Since the first “test tube baby” was born over 40 years ago, in vitro fertilization and other assisted reproductive technologies (ARTs) have advanced in extraordinary ways, producing millions of babies. About 20% of Americans use infertility services, and that number is growing. ARTs enable gay and lesbian couples, single parents, and now others to have offspring. Prospective parents can also use preimplantation genetic diagnosis to avoid passing on certain mutations to their children and to avoid abortions of fetuses with these mutations. Other future parents routinely choose the sex of their child and whether to give birth to twins. In the United States, these procedures are largely unregulated, and a large commercial market has rapidly grown, using “egg donors,” buying and selling human eggs and sperm, and using gestational surrogates. Potential parents; policymakers; doctors, including reproductive endocrinologists; and others thus face critical complex questions about the use—or possible misuse—of ARTs. This book examines ethical, social, and policy questions about these crucial technologies. Based on in-depth interviews, Robert Klitzman explores how doctors and patients struggle with quandaries of whether, when, and how to use ARTs. He articulates the full range of these crucial issues, from economic pressures to moral and social challenges of making decisions that will profoundly shape these offspring. The book explores, too, broader social and moral questions regarding gene editing, CRISPR, and eugenics. Klitzman argues for closer regulation of these technologies, which are altering future generations and the human species as a whole.