A medical power of attorney is a legal document where one person, the principal, gives another person, the agent, the right to make medical decisions for the principal when he is incapacitated. The American Bar Association recommends confirming a potential agent's willingness to carry out the document before finalizing it.
A medical power of attorney specifies the medical treatment the principal wishes to receive in the event he is unable to communicate his wishes. The agent is responsible for carrying out the directives in the document and is the decision maker for medical decisions on behalf of the principal. There is usually only one appointed agent, though it is common to appoint successor agents in case the primary agent is unavailable. These documents resolve confusion for physicians and prevent issues resulting from familial disagreements.