In 1998, researchers at the University of Wisconsin isolated human embryonic stem cells in the laboratory. They showed that these cells, which can become any kind of cell or tissue, could live and thrive outside the human body. This landmark discovery opened the door to a new era in biology and medicine and set off a furious political controversy that continues to make headlines today. "Christopher Scott, a scientist with a journalist's skill at clear explanation has provided exactly what is needed in this book... a reliable, balanced, and thoughtful account of the biology of stem cells." From the Foreword by Donald Kennedy, Editor of Science "If you want to read one book about both the science and social impact of stem cell research, this is the book. It is crystal clear, candid and highly informative. It is terrific." Michael Gazzaniga, author of The Ethical Brain "Scott has provided a firmly grounded schooling in our current understandings and misunderstandings of how stem cell research may play out in creating new forms of therapy for currently untreatable diseases." Paul Berg, Nobel laureate, author of Dealing with Genes "In this engaging book, biologists give their first-hand accounts of why their work generates such passion and attention. If you need an introduction to the intricacies of stem cell science and the ethical arguments behind the debates, this is a fine place to begin." Laurie Zoloth, Director, Center for Bioethics, Northwestern University.