Cloning technology was invented during the twentieth century and now stands poised to help define the twenty-first. Almost everyone has heard of Dolly, the cloned sheep born in 1996 but what about the rapid progress made since then? Scientists now count horses, cows, cats, and dogs, among the many animals they can clone. This progress raises a host of questions. Are you comfortable drinking milk or eating meat from a cloned cow? Should we clone extinct or endangered species? Will the April 2005 birth of Snuppy, the world's first cloned dog, usher in a new era of cloned pets? Should we clone embryos to generate embryonic stem cells and help develop medical therapies? And perhaps the most important question of all: when, if ever, will this progress lead to the first cloned human?

Although scientists are nearly unified in their opposition to cloning humans for reproductive purposes, on-going research with other goals in mind, makes this prospect likely, if not inevitable. For the most part, this research is driven by the hope that cloning technology will have significant health benefits, perhaps leading to transplantation therapies using embryonic stem cells specifically tailored to individual patients. Of course, if a cloned human is ever born, the desire for fame will almost certainly play a role. Looking back to the media frenzy surrounding the birth of the first test tube baby in 1978 or the clamor surrounding the birth of Dolly, it is not hard to imagine the furor that a cloned human baby would generate.

As modern biotechnology is increasingly applied to humans, it poses important questions for society to address. Should we, perhaps in the relatively near future, allow infertile couples or single mothers to use cloning technology try to produce a child? Should we, in the longer-term, permits parents to use cloning technology not just to have children, but to have children with specific genetic modifications or enhancements? Debates on cloning technology and its implications are, all too often, hijacked by advocates or opponents who skew the science to fit a particular view. Although the details of cloning research are complex, the general technique is not particularly difficult to understand. And understanding this general technique and its consequences is more than enough to participate fully in these important debates and to see through the many myths clouding discussions of cloning.