Prognostication, the process of formulating and communicating a prognosis, is no longer considered by most physicians to be an essential task in caring for patients with serious illness. Because of this fact, it is not surprising to find that when physicians attempt to engage in prognostication, they do it poorly. What may be surprising to those outside the medical community is the extent to which professional norms have developed which actively discourage physicians from engaging in prognostication. This article explores the causes of this state of affairs and the justifications offered for it. The conclusion is reached that physicians have a professional responsibility to competently engage in prognostication based upon the doctrine of informed consent, and that a failure or refusal to do so has not only potential legal ramifications, but serious negative implications for many of the core issues in bioethics, such as the use of advance directives, palliative medicine, and medical futility.