The Hippocratic Oath is an oath traditionally taken by physicians, in which certain ethical guidelines are laid out. One traditional version is below but there are others.1
I swear by Apollo the physician, by ∆sculapius, Hygeia, and Panacea, and I take to witness all the gods, all the goddesses, to keep according to my ability and my judgement, the following Oath.
"To consider dear to me as my parents him who taught me this art; to live in common with him and if necessary to share my goods with him; to look upon his children as my own brothers, to teach them this art if they so desire without fee or written promise; to impart to my sons and the sons of the master who taught me and the disciples who have enrolled themselves and have agreed to the rules of the profession, but to these alone the precepts and the instruction. I will prescribe regimens for the good of my patients according to my ability and my judgement and never do harm to anyone. To please no one will I prescribe a deadly drug nor give advice which may cause his death. Nor will I give a woman a pessary to procure abortion. But I will preserve the purity of my life and my art. I will not cut for stone, even for patients in whom the disease is manifest; I will leave this operation to be performed by practitioners, specialists in this art. In every house where I come I will enter only for the good of my patients, keeping myself far from all intentional ill-doing and all seduction and especially from the pleasures of love with women or with men, be they free or slaves. All that may come to my knowledge in the exercise of my profession or in daily commerce with men, which ought not to be spread abroad, I will keep secret and will never reveal. If I keep this oath faithfully, may I enjoy my life and practice my art, respected by all men and in all times; but if I swerve from it or violate it, may the reverse be my lot."
Several parts of the Oath have been removed or re-worded over the years in various countries, schools, and societies but the Oath still remains one of the few elements of medicine that has lasted so long. Most schools administer some form of oath, but the great majority no longer use this ancient version which praises Pagan gods, advocates teaching of men but not women, and forbids cutting, abortion, and euthanasia.1 Also missing from the ancient Oath and many modern versions are complex, new landmines such as dealing with HMO's, living wills , whether morning-after pills are technically closer to prophylaxis or an abortion (they are different from RU-486), experiments on humans who give informed consent, or genetic research. Some doctors prefer to drop all pretenses of oaths, since medical boards and courtrooms are the real forces where unethical conduct is judged today. Following is a listing of the specific promises and a modern perspective:
- To support my teacher if necessary. Professional courtesy (not charging families of physicians for one's services) is perhaps the last trace of this item and has largely been abandoned.
- To teach medicine to the sons of my teacher. In the past, medical schools would give preferential consideration to the children of physicians. This too has largely disappeared.
- To practice and prescribe to the best of my ability for the good of my patients, and to try to avoid harming them. This beneficial intention is the purpose of the physician. However, this item is still invoked in discussions of euthanasia.
To never deliberately do harm to anyone for anyone else's interest. Physician organizations in the U.S. and most other countries have strongly denounced physician participation in legal executions.
- To never attempt to induce an abortion. The wide availability of abortions in much of the world suggests that many physicians no longer feel bound by this.
- To avoid violating the morals of my community. Many licensing agencies will revoke a physician's license for offending the morals of the community ("moral turpitude").
To avoid attempting to do things that other specialists can do better. The "stones" referred to are kidney stones or bladder stones , removal of which was judged too difficult for general practitioners, and therefore was left for specialists. It is interesting how early the value of specialization was recognized. The range of knowledge and skills needed for the range of human problems has always made it impossible for any single physician to maintain expertise in all areas.
- To keep the good of the patient as the highest priority. There may be other conflicting "good purposes," such as community welfare, conserving economic resources, supporting the criminal justice system, or simply making money for the physician or his employer that provide recurring challenges to physicians.
- To avoid sexual relationships or other inappropriate entanglements with patients and families. The value of avoiding conflicts of interest has never been questioned.
To keep confidential what I learn about my patients. Confidentiality continues to be valued and protected, but governments and third-party payors have occasionally encroached upon it.
In the 1970s cultural and social forces induced many American medical schools to abandon the Hippocratic Oath as part of graduation ceremonies, usually substituting a version modified to something considered more politically up to date, or an alternate pledge like the Oath or Prayer of Maimonides.
The Hippocratic Oath has been updated by the Declaration of Geneva, q.v. In the United Kingdom, the General Medical Council provides clear modern guidance in the form of its 'duties of a doctor' and 'Good Medical Practice' statements.
1 The Hippocratic Oath Today: Meaningless Relic or Invaluable Moral Guide?
A history of the oath - summary of a New Engl. J. Med. article
 - NOVA Online discussion with responses from doctors as well as 2 versions of the oath