Although the term Living Will may indicate that it is a Will, in reality, it is more similar to a Power of Attorney than a Will. Therefore, don't be confused by the title of the document. The purpose of a Living Will is to allow you to make decisions about life support and direct others to implement your desires in that regard.
Living Wills are needed because advances in medicine allow doctors to prolong and sustain life although the person will not recover from a persistent vegetative state. Some people would not desire to remain in that state while others would. Extending life when death is imminent to some people is only extending the suffering and prolonging of the dying process. The Living Will allows you to make the decision of whether life-prolonging medical or surgical procedures are to be continued, withheld, or withdrawn, as well as when artificial feeding and fluids are to be used or withheld. It allows you to express your wishes prior to being incapacitated. Your physicians or health care providers are directed by the Living Will to follow your instructions. You may revoke the Living Will prior to becoming incapacitated. The procedures for revocation are provided in the forms listed.
To be valid, the proper form must be used for your state and it must be executed in compliance with the laws of your state. Some states require two witnesses to witness your signature or that the form be signed in the presence of a Notary Public, or both. The forms provided on this site indicate which is required.
If the form provides for the appointment of an agent, the agent appointed should not also be a witness to your signature. The agent appointed to carry out your wishes is sometimes called a Health Care Representative.
The Living Will generally becomes operative when it is provided to your physician or health care provider AND you are incapable of making health care decisions for yourself, such as where you are permanently unconscious or terminally ill and unable to communicate.