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 as part of an Advance Health Care Directive, which allows an individual to outline their preferences for medical treatment in the event they are unable to communicate their wishes due to a medical emergency. This document 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's laws regarding living wills and other advance directives are found in Title 50, Chapter 9 of the Montana Code Annotated (MCA). The state also recognizes Do Not Resuscitate (DNR) orders, which are separate documents that instruct medical personnel not to perform CPR if the patient's breathing or heartbeat stops. It is important for individuals to ensure that their living wills and other advance directives comply with Montana law to be legally effective. An attorney can assist in drafting these documents to ensure they accurately reflect the individual's wishes and meet all legal requirements.