A living will—also known as an Advance Health Care Directive—is a document in which the declarant or principal (person making the living will) specifies what kind of medical treatment the declarant does and does not want if the declarant has a medical emergency and is unable to communicate those wishes. A living will may direct health care providers to administer, withhold, or withdraw life-sustaining treatments if the declarant is in a terminal or irreversible condition.

Laws and terminology for documents related to living wills, Advance Health Care Directives, Do Not Resuscitate orders (DNRs), and other health care documents vary from state to state. These laws are generally located in a state’s statutes—often in the probate code or estates code.

In Montana, a living will is recognized under the Montana Rights of the Terminally Ill Act. This legal document, also known as an Advance Health Care Directive, allows an individual (the principal) to outline their preferences for medical treatment in the event that they are unable to communicate due to a medical emergency. The living will can include instructions on the administration, withholding, or withdrawal of life-sustaining treatments if the individual is in a terminal condition or in a state that is considered irreversible. Montana law also recognizes Do Not Resuscitate (DNR) orders, which instruct medical personnel not to perform CPR if the patient's breathing or heart stops. It is important for individuals to ensure that their living wills and other advance directives comply with Montana state statutes to be legally enforceable. An attorney can provide guidance on creating a living will that accurately reflects an individual's wishes and meets all legal requirements in Montana.