A durable power of attorney is a legal document in which one person grants another person the authority to make medical decisions if he or she becomes unable to do so. The person chosen as the health care agent (or health care proxy or surrogate) should understand and respect the person's wishes about medical treatment.

In writing a durable power of attorney, a person may specify how decisions are to be made. A durable power of attorney may also give the health care agent the authority to make other types of decisions, including financial ones.

A person must be mentally competent to complete this document. For this reason, a person with a progressive brain disorder (such as Alzheimer's disease) should consider drawing up this document as early as possible to avoid later difficulties as judgment becomes impaired.

The document should be stored in a safe but easily accessible place, and copies should be provided to one's doctor, attorney, and loved ones.