Human cloning is regularly in the news. And an article hyping the potential of stem cells seems to spring up every week. This book is aimed at an audience of people without a background in cell and molecular biology who want to make sense of these subjects so that they can make intelligent decisions about their health and that of their families. My emphasis is on principles, not on jargon; on the people who made (and are making) the exciting discoveries, not on a dry recitation of facts. Some of the questions that the book deals with are: How does a group of seemingly identical embryonic cells manage to give rise to tissues as different from one another as the brain and the heart? Can this phenomenon be reversed; can scientists make a heart or nerve cell into one from an embryo with the potential for forming any tissue in the body? What exactly is a clone? How easy it to clone an animal? A human? Should we clone humans? Are there human clones already walking among us? What are some of the ethical and moral issues involved? What kinds of stem cells are there and what are the advantages and drawbacks of each type for therapy? What diseases can we cure now with stem cells, and which ones might we expect to address in the future? Could stem cells be used to reverse aging? Could we grow new organs via stem cells? What are the costs and benefits of banking umbilical cord cells? This book represents my attempt to answer these and related questions by conveying the excitement of cloning and stem cell research to as wide an audience as possible without burdening them with minutia and technical details.