This chapter presents a case study of a 45-year-old woman admitted for laparoscopic cholecystectomy as an example for the occurrence of medical errors. A competent anesthesiologist would recognize the classic signs of anaphylaxis. Modern medical ethics emphasizes four guiding principles; patient autonomy, beneficence, nonmaleficence, and justice. The ethical principle of justice requires that patients be treated equally, thus patients are entitled to the truth regardless of the views of their physicians or the policies of the institution in which they receive care. Adherence to established ethical principles and the strong arguments in favor of open, transparent medical error disclosure are hindered by physicians' fears and mistrust of the legal system. Raising awareness amongst anesthesiologists of the ethical arguments involved in error disclosure, as well as the provision of strong institutional support and training in error disclosure, will help to improve error disclosure practices and enhance patient safety.