The broad sweep of medicine’s history since the middle of the 20th century has been one of improvement in the care of patients, but that progress has not been uniform. The very processes that lead to important advances in medical care also fail; some of these failures are catastrophic. Patient welfare and improvement in health or functional status comprise the central goal of medical care, yet harm to patients is an ever-present risk, especially in the case of employing novel interventions. Of the processes that have improved medical care, formal clinical research is best known in bioethics circles since it has the most robust mechanisms for the protection of subjects. Other processes involve modifications to existing treatments or wholly new interventions or approaches within the course of patient care. Here the mechanisms for ethical and safety oversight are less well defined.