Depending on the jurisdiction, advance directives are also known as living wills, power of attorney for health care, personal directives, and health care proxies.
Advance directives are one reflection of the strong commitment to the principle of respect for autonomy in many Western cultures. They provide a means of communicating how decision making for an individual should be approached at the time when that person is unable to make decisions themselves.
These documents can guide decision making in various ways; by indicating another individual who should make decisions on behalf of the directive’s author (a substitute decision maker), by laying out the values and principles that should be reflected in decisions, or by giving specific instructions for particular scenarios.
In most jurisdictions, there is guidance regarding the bases upon which decisions for others should be made. The primary source of guidance is an individual’s explicitly stated wishes. Should there be no previously expressed wishes relevant to the situation the individual is in, substitute decision makers are instructed to turn to an individual’s values and principles. And if these are not available or relevant, then as a last resort the individual’s presumed best interests should guide action.