A Living Will, also known as an Advance Health Care Directive, is a legally binding document that outlines specific wishes in regards to treatment if the patient is incapacitated and unable to give informed consent. Often a Health Care Proxy or Health Care Power of Attorney is appointed to carry out the patient’s wishes. Often they are drawn up by legal professionals, but you can find standard formats online to fill out, and often they are offered in hospitals on admission. Usually the document is notarized and witnessed, as well.
Make sure the Living Will you draw up meets legal requirements, as if it does not, it may be contested.