The term 'living will', whilst helping people to understand the concept, is somewhat misleading in that, unlike a will, it does not deal with money or property. Moreover, it can relate to all future treatment, not just that which may be immediately life-saving.
An advance decision, as it is formally known is legally binding in England and Wales. Except in the case where the individual decides to refuse life-saving treatment, it does not have to be written down, although most are and a written document is less likely to be challenged.
Why make an advance decision?
If you have strong feelings about particular types of treatment, you may wish to make an advance decision.
You may want to refuse a blood transfusion, or an amputation. More commonly, if you've been told you have a terminal illness or dementia, you may wish to indicate which types of treatment you wouldn't want to receive in the future.
An advance decision can give you peace of mind knowing your wishes won't be ignored.