Aim: To review relevant ethical principles in dentistry and relate them to endodontic practice. Summary: In dentistry, as in other areas of healthcare, the clinician has to deal with various legal and ethical issues. Whilst legal issues are often discussed, comparatively little is known about the ethical issues that govern a clinician's actions. In this article, an attempt is made to clarify the distinctions between ethical principles and legal rules, and to highlight their relationship. In general, five main ethical principles in dentistry have been outlined: autonomy, non-maleficence, beneficence, veracity and justice. Since there are specific ethical issues in daily endodontic practice (such as informed consent to endodontic treatment, the increasing use of implants instead of root canal treatment and the relationship between oral and general health), an attempt is made to co-relate these general principles to endodontics. Additional discussion and examples are suggested including guidelines on decision-making based on ethical principles. Key learning points: • Endodontic treatment is governed by ethical and legal principles. • The foundations for both law and ethics were laid out in ancient times but are constantly modified by society. Keywords: endodontics, ethics, principles