This paper reviews the advent of unilateral do-not-resuscitate orders. Unilateral do-not-resuscitate policies presume that cardiopulmonary resuscitation is a medical therapy and that physicians have no obligation to undertake a medical therapy that does not offer achievable and appropriate goals. Four do-not-resuscitate policies from U.S. hospitals and some of the significant published proposals are reviewed. We conclude that anything other than a physiologic definition of futility is indefensible because of imposed value judgments, imprecise definitions of quantitative and qualitative futility, inexact data, lack of certitude of economic benefit, and the role of autonomy for the patient and physician.