Dementia is one of the great and growing facts of our age. Modern medicine has spared us to grow old, and when we grow old, dementia is waiting for many of us. It will steal our neurones, our memories, our independence and our ability to perceive our relationships (if not the relationships themselves). It may even (there’s an important debate about this) rob us of ourselves, or allow us to remake ourselves. By and large Western governments, seeing the scary demographics of dementia, have buried their heads in the sand. Insufficient money has been set aside to deal with dementia. It often seems as if, since patients with dementia can’t complain, or can’t complain on the statutory forms, they are presumed not to exist. Even when dementia is acknowledged, it is precisely that—dementia: the problem—that is acknowledged, rather than the people who have the condition. It is attitudes as well as organic disease which steal personhood. So: dementia is unfashionable and frightening. Law and philosophy are slavish followers of fashion. They haven’t given dementia and its victims (patients, carers, communities, all of us) anything like the attention they deserve. That’s a shame. A shame not just for the governments (which can use all the help they can get), and for the victims (for whom even wrong-headed attention would be a comfort), but for the lawyers and the philosophers. They’re missing some fascinating, deeply repercussive problems: problems that take us deep into what it means to be human; what it means to legislate; when it is appropriate for the state or anyone else to step into the shoes of another. And doctors, too, are forced by dementia to face the questions that their usual busy-ness helps them ignore: why treat at all? Whom should we treat? Who, indeed, is the patient lying in the hospital bed? This book is an attempt to confront these questions. It has to be a big book, and it has to be a multidisciplinary book. Such work as there has been on the law and ethics of dementia has often suffered because the lawyers haven’t read the ethicists, the ethicists haven’t read the lawyers, neither have read the doctors and even many of the doctors have never had to break the news of the diagnosis to a patient or a spouse, or deal in the early hours with a patient who has started to masturbate in front of the nurses. Some of the juxtapositions will jar. Good. Details of drug doses rub shoulders with Kant. That’s how it should be. They need each other for credibility. An essay about the ethics of dangling therapeutic hopes before the noses of desperate patients is better for sharing space with a piece about what those hopes actually are. Dementia diagnosis, therapy, care, philosophy, economics and law are all in their infancy. Most of the leading thinkers in the field (which includes all of the contributors to this book) are finding their way. Rarely is there any definitively right or wrong answer. That means that the book contains opinions, unreferenced assertions, debates and downright contradictions. If it didn’t, it wouldn’t represent the subject properly. The diseases called, generically, dementia, are mysterious. They generate baffling problems.