Every day we hear news about medical or scientific breakthroughs and the complex ethical issues they raise. Feats that were never before possible including cloning, genetically modifying food, mapping human chromosomes and using animal organs for human transplants have opened up a Pandora's box of ethical questions.Technology is advancing at such a rate that the issue is not so much what we can do but rather whether we will do it. According to Margaret Somerville, a leading international authority on medicine, ethics and the law, society must set ethically acceptable limits on scientific advances. In this controversial, timely and much-anticipated book, Professor Somerville sheds light on the urgent ethical and legal questions that vie for our attention. Along the way, she calls upon us to recognize the mysteries that lie at the heart of our lives and the metaphysical reality that gives meaning to life.