A living will is a legal document, which lets a patient decide whether or not to be kept on artificial life support. Often, these documents also appoint someone to take important health care decisions on behalf of the patient. A living will could be a very broad or a narrow document, prepared according to the wishes of the patient. The will is a living declaration of peoples wishes when they meet with serious accident or ailments. It is primarily directed to medical personnel about the type of care the patient wishes to have, or wishes not to have, under situations of terminal illness.

The document commonly includes the kinds of medical procedures that are usually administered to patients who are seriously ill. These may include transfusions of blood and blood products, cardiopulmonary resuscitation, diagnostic tests, dialysis, administration of drugs and surgeries.

The living will should be given careful thought, and must be discussed by the patient's family, physician, and care providers. The living will involves both the patient's family and loved ones, who help in its implementation. It is mandatory for the will to be dated and signed before two witnesses.

The living will declaration can also include issues of pain medication, food, and water. Many medical experts feel that relief from pain and discomfort are procedures that people wish to have. But these are not considered life-prolonging treatments. In some states, however, food and water may be considered life prolonging and the consideration to forego them may fall within the rights of the patient.

The living will may be drafted on standardized forms, with or without the assistance of an attorney. The document may be revoked in writing, or orally, by either the patient or by a designated proxy, also called a surrogate. If the patient does not specify a particular element of treatment or treatment withdrawal, then it is not included. It is very important that living wills be as specific and detailed as possible.