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 New Jersey, a living will is legally referred to as an Advance Directive for Health Care. This document allows an individual, known as the declarant, to outline their preferences for medical treatment in the event that they are unable to communicate their wishes due to incapacity. The Advance Directive can specify whether the declarant wishes to receive, withhold, or withdraw life-sustaining treatment if they are in a terminal condition or permanently unconscious. New Jersey law recognizes two main components of an Advance Directive: the Proxy Directive (Durable Power of Attorney for Health Care), which designates a health care representative to make decisions on the declarant's behalf, and the Instruction Directive (Living Will), which outlines the declarant's treatment preferences. These documents must be in writing, signed, and either notarized or witnessed by two individuals. The relevant statutes governing Advance Directives in New Jersey can be found in the New Jersey Statutes Annotated (N.J.S.A.) 26:2H-53 to 26:2H-78, which is part of the New Jersey Advance Directives for Health Care Act.