When you are ill, you can usually discuss treatment options with your doctor and then jointly reach a decision about your future care. However, you may be admitted to hospital when unconscious or unable, on a temporary or permanent basis, to make your own decisions about your treatment or communicate your wishes. This may happen, for example, if you have a car accident or a stroke or develop dementia. To use the technical term – you would 'lack mental capacity' to make an informed decision and/or communicate your wishes. In such situations, doctors have a legal and ethical obligation to act in your best interests.
One exception to this is if you have made an advance decision refusing treatment. If this decision is valid and applicable to the circumstances, medical professionals providing your care may be bound to follow it.
A Living Will is not a Will leaving property to family and friends, but is a document which can be used to record any advance decisions that you may have made.
A Living Will can also be used to record your preferences and to indicate what medical treatment or care you would like to receive ('advance statements').