Everybody recognizes that most of the problems in medical ethics arise, these days, from innovations in medical technology. We would not have had to lay down laws or ethical guidelines about assisted reproduction had it not been for the new technology of in vitro fertilization, which produced the first IVF baby in 1978. We would not be currently anxious about the ethics of possible human cloning, had it not been for the production in Edinburgh of Dolly, the lamb whose birth resulted from the removal of a mammary gland cell from an adult sheep. So the question is whether there is some research into developing technology that is too dangerous, that will lead to consequences too dramatic for humanity, for the research itself to be permitted. Should there be control over what technological innovation should be permitted?