If a patient is no longer able to make or express their own decisions, has not provided any written guidance, and has not assigned that right to an agent or alternate, others, including health care providers and institutions, may make those decisions on the patient's behalf. Sometimes a court may appoint a guardian. The decisions of these third parties might not exactly comply with those the patient would have made when still competent. Therefore, more people are stating their health care choices in writing in advance.

An advance directive is a document stating a person's health care choices or naming someone to make the choices on their behalf if the person becomes unable to do so. The specific legal documents by which this is accomplished are a Living Will and a Durable Power of Attorney for Health Care (DPA).

A thorough advance directive describes the kind of medical treatment a person would desire for different levels of illness or injury. For example, the directive would describe what kind of care a person would want if critically ill or injured, had a terminal condition or was permanently unconscious. An advance directive can specify both the medical treatments to be provided under certain circumstances and those to be withheld. Alternately, the person can also state that all life-sustaining procedures are to be used, no matter how ill the person becomes.

In order to make knowledgeable decisions, a person should talk to: their doctor about the effects of withholding or withdrawing different treatments, including life-sustaining procedures; their family, and; their attorney, if appropriate.
 

Even without such provisions, doctors and medical facilities usually consult close family members. In this manner, consensus is usually reached about treatment options. However, on occasion family members either may not know a patient's wishes or be unable to reach consensus. As a result, a doctor may become the decision-maker or the courts may have to resolve any disagreement.

While the decisions should be guided by the patient's desires, if those desires have not been communicated, even verbally, decisions made may be contrary to the patient's wishes. Family members and friends may endure unnecessary strife and grief attempting to make decisions without knowing the patient's preferences. It is better for all parties involved for a person to make their own values and preferences known and appoint an agent ahead of time through an advance directive.

Should everyone have an advance directive? Advance directives are most often created by elderly or seriously ill patients in order to reduce their suffering and provide the peace of mind that they are in control with regard to dying with dignity. However, because an accident or serious illness can happen suddenly, anyone may want to consider creating an advance directive.