In this important new book, a number of ethicists expound on the issue of medically assisted death and, in particular, on the issue of whether it is morally permissible to hasten the death of those who are suffering from a medical condition but, because of their diminished mental capacities, are unable to ask that anything be done about that suffering. This essential new book is concerned with the issue of euthanasia and associated legislative and health care issues. The book focuses on a central strand in the debate over medically assisted death, the so called 'slippery slope' argument, and in particular, on one important aspect of the downward slope of this argument: hastening the death of those individuals who appear to be suffering greatly from their medical condition but are unable to request that we do anything about that suffering because of their diminished mental capacities. Slippery slope concerns have been raised in many countries, including Britain, the Netherlands, Canada, and the United States. This book concentrates most of its attention on the latter two countries.