What if you become ill and are unable to speak for yourself? An advanced health care directive is the best way to make sure that your health care wishes are followed. Among other things, a health care directive allows you to appoint another person to be your health care agent. This person will have legal authority to make decisions about your medical care and living arrangements should you become unable to make those decisions yourself. You may have certain wishes, for example, a desire not to receive treatment that only prolongs the dying process if you are seriously ill. Your doctor and your agent must follow your instructions within the limits of generally accepted health care standards. This document also allows you to express your requests about organ and tissue donation.