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The 4 Pillars of Medical Ethics, With Examples and How to Use Them
The four pillars of medical ethics are respect for autonomy, beneficence, nonmaleficence and justice. Tom Beauchamp and James Childress set them out in Principles of Biomedical Ethics, first published in 1979 (UW Department of Bioethics and Humanities). They are a way to name what is at stake, not a formula, and most hard cases are two of them pulling in different directions.
If you searched for “principles of medical ethics,” you may want the American Medical Association's nine Principles instead. They are a different list, summarized below. This page covers both, with examples, the common conflicts and how to use the pillars on an interview question. Sources were read October 31, 2026. Examples and the example answer are ours.
The four pillars of medical ethics in plain words
| Pillar | In plain words | In the clinic | As an interview prompt |
|---|---|---|---|
| Respect for autonomy | In plain words: A patient with decision-making capacity decides what happens to their own body, after real information and without pressure. | In the clinic: Explaining the risks and options of a surgery, then accepting a capable patient's choice to wait. | As an interview prompt: A capable adult refuses a treatment you believe would help. |
| Beneficence | In plain words: Act for the patient's good: provide benefit, and take positive steps to prevent and remove harm. | In the clinic: Recommending a vaccine or a screening test because the evidence shows it helps. | As an interview prompt: A friend's parent asks you to talk their teenager into getting care. |
| Nonmaleficence | In plain words: Do not create harm or injury, by acting or by failing to act. Every treatment's harms are weighed against its benefits. | In the clinic: Stopping a medication when its side effects outweigh what it does for the patient. | As an interview prompt: A patient asks for antibiotics for a cold. |
| Justice | In plain words: Fairness: similar cases are treated alike, and scarce resources are shared by fair rules, not by who asks loudest. | In the clinic: Allocating ICU beds or organs by medical need and likely benefit. | As an interview prompt: One donated kidney, two patients who need it. |
Why they matter: the pillars give patients, clinicians and ethics committees a shared language for a hard case, so a disagreement becomes a question of which duty should weigh more here, not whose instinct wins. Respect for autonomy is what informed consent puts into practice. UW's definitions are worth reading in full. Nonmaleficence means not creating harm or injury “either through acts of commission or omission,” and beneficence means providers have a duty to benefit the patient and to take positive steps to prevent and remove harm. Justice is usually defined as a form of fairness (UW Bioethics).
Medical schools look for this kind of reasoning. The AAMC's premed competency for ethical responsibility includes considering “multiple and/or conflicting principles and values to inform decisions” and resisting pressure to act unethically (AAMC premed competencies). See our guide to the AAMC competencies for the rest.
When the pillars conflict
One pillar alone rarely decides a case. These are the five collisions that come up most, with the direction the official guidance gives where it gives one. Two of them set a pillar against a duty that is not one of the four: stewardship of shared resources and confidentiality.
| Conflict | Example | Where guidance points |
|---|---|---|
| Autonomy vs beneficence | Example: A capable adult refuses a blood transfusion that would likely save their life. | Where guidance points: The AMA Code says a capable patient may decline any intervention, even one expected to lead to death. Check capacity and understanding, then respect the choice. |
| Beneficence vs nonmaleficence | Example: A chemotherapy plan could extend life but with heavy side effects. | Where guidance points: No rule settles it. Weigh benefit against harm with the patient's own goals, and revisit as things change. |
| Autonomy vs stewardship | Example: A patient insists on an expensive scan that will not change their care. | Where guidance points: The AMA Code asks physicians to be prudent stewards of shared resources, to choose the option that uses fewer when benefit is similar, and to be open about it. Explain why, and offer what will help. |
| Beneficence vs justice | Example: Two patients need the last ICU bed, and the one you are treating is less likely to benefit. | Where guidance points: The AMA Code bases allocation of scarce resources on medical need: urgency, likelihood and duration of benefit, and change in quality of life. |
| Confidentiality vs others' safety | Example: A patient says he plans to hurt a specific person. | Where guidance points: HHS says providers may disclose what is needed to someone who can prevent or lessen a serious and imminent threat, without the patient's permission. |
Sources for the table: the AMA Code on withholding or withdrawing treatment, on stewardship of health care resources and on allocating limited resources, and HHS guidance on serious and imminent threats. The confidentiality row is covered in full in patient confidentiality, and the Tarasoff case behind it in duty to warn. For sixteen fuller cases, see ethical dilemmas in medicine.
The AMA's nine Principles of Medical Ethics
The AMA's list is older than the four pillars and works differently. It describes a physician's duties rather than a way to weigh them. The AMA says its Principles “are not laws, but standards of conduct that define the essentials of honorable behavior for the physician,” and that a physician's responsibility is to patients first and foremost. They were adopted in June 1957 and revised in 1980 and 2001 (AMA Principles of Medical Ethics).
The nine AMA Principles, summarized in our words
- Competent care with compassion and respect for human dignity and rights.
- Professionalism and honesty, and reporting colleagues who are incompetent or engage in fraud.
- Respect for the law, and working to change laws that go against patients' best interests.
- Respect for the rights of patients and colleagues, and protecting patient confidences and privacy.
- Lifelong learning, sharing knowledge and consulting other professionals when needed.
- Freedom, except in emergencies, to choose whom to serve and where to practice.
- Taking part in improving the community and public health.
- Treating responsibility to the patient as paramount.
- Supporting access to medical care for all people.
The two lists overlap without matching. Principle I's competent, compassionate care is close to beneficence, VIII puts the patient first and IX, access to care, is a form of justice. Principle IV adds a duty the four pillars do not name on their own: confidentiality. Read the original wording before you quote it.
How to use the four pillars in an interview
In an MMI ethics station, a panel interview or Casper, naming a pillar shows you know the vocabulary. Using it to reach a decision is what scores. Our four steps:
- Name the people and the facts. Who is affected, what do you know, and what do you still need to ask? Capacity is often the first missing fact.
- Name the two pillars in tension. One sentence is enough: this is autonomy against beneficence. Listing all four and stopping scores nothing.
- Weigh the options out loud. Give two or three real options and what each costs, including the one you will not choose.
- Choose, and say what happens next. A clear decision, who you would involve, and how you would follow up or revisit it.
For 40 prompts to practice on, see MMI ethics questions. For a contested question where the pillars collide, try medical aid in dying. Casper's version is in our Casper ethics questions.
Practice question: a capable patient refuses treatment
“A capable adult patient refuses a blood transfusion that would likely save his life. What do you do?”
The classic autonomy vs beneficence case. A strong answer checks capacity and understanding, explores the reason, offers alternatives and respects a capable refusal.
Example answer written by Confetto (the applicant is invented)
This is a conflict between respecting his autonomy and wanting to do him good. Before anything else I would make sure I understand his decision and that he has the capacity to make it.
So I would sit down with him privately, ask what is behind the refusal and check that he understands what the transfusion is for and what is likely to happen without it. If the reason is a religious belief, I would ask what is and is not acceptable to him, because there are often options, like medications that boost his own blood count or techniques that reduce blood loss, that we can use.
I would also check his capacity properly, with the senior physician, since a lot depends on it. If he is capable and informed, I would respect his choice, document the conversation, keep caring for him with every other option, and tell him he can change his mind at any point.
What I would not do is pressure him or go around him. If he lacked capacity, the decision would move to his surrogate or the team, guided by what he would have wanted.
Sources: UW Department of Bioethics and Humanities, the AMA Code of Medical Ethics, HHS and the AAMC, linked throughout and checked October 31, 2026.
Frequently asked questions
What are the 4 pillars of medical ethics?
Respect for autonomy, beneficence, nonmaleficence and justice. Tom Beauchamp and James Childress set them out in Principles of Biomedical Ethics, first published in 1979. See UW Bioethics on the principles.
What is the difference between beneficence and nonmaleficence?
Beneficence is a duty to do good and to prevent and remove harm. Nonmaleficence is a duty not to cause harm, by acting or by failing to act. Most treatments involve both, so you weigh benefit against harm. See the definitions.
What are the AMA's principles of medical ethics?
A separate list of nine standards adopted by the American Medical Association in 1957 and revised in 1980 and 2001. The AMA says they are not laws but standards of conduct. Read the AMA Principles of Medical Ethics.
Which principle is most important?
None always wins. The principles are a way to name what is at stake. Real cases are decided by the facts, the patient's values and the law, often with two principles pulling in different directions.
Should I name the four principles in a medical school interview?
Use them as a label in one sentence, then reason through the case. Interviewers want to see you weigh options and choose. Our MMI ethics guide has 40 questions to practice on. Practice with MMI ethics questions.