Recent recommendations that physicians be allowed to withhold cardiopulmonary resuscitation, without patient consent, from patients for whom it would be futile have drawn objections that such unilateral judgments would undermine respect for patient autonomy. These objections assume that since futility determinations involve value judgments, patient input is always required. However, certain sorts of value judgments must be made unilaterally by physicians as part of reasonable medical practice. Moreover, the mixed messages inherent in requesting patient consent to withhold futile therapy serve to undermine rather than to enhance autonomous choice. Real patient interests can better be served by a broad public dialogue around judgments of medical reasonableness and medical futility, rather than concern for the form but not the substance of patient autonomy.