Background No studies have been conducted in Mexico to ascertain what ethical problems doctors working at hospitals deal with. This article aims to describe the ethical conflicts most commonly identified by Mexican internists and the importance they attribute to each of these conflicts. Methods Voluntary survey to the members of the Internal Medicine Association of Mexico. Results Responses were submitted by 347 internists. Half of those face ethical conflicts almost always or frequently. The most commonplace and relevant conflicts are those (...) resulting from the clinical relationship (communication, confidentiality, informed consent, assessment of mental capacity, decisions involving incapacitated patients, and conflicts with family members), and secondly those problems related with the end of life (palliative care, withholding or withdrawing treatment, and “No CPR orders”). To resolve conflicts they seek support through protocols, Institutional Ethics Committees (IECs), and consultations with colleagues and, occasionally, with bioethics experts. Protocols and IECs are the tools most in demand among them. Conclusions 1) the most frequent and relevant conflicts are those caused by the clinical relationship, above all those due to doctor–patient communication, and secondly those due to problems which arise at the end of life; 2) though nearly all of them have doubts about how to resolve conflicts, the vast majority are satisfied with the way in which they do so; 3) to deal with conflicts, they seek support mainly in protocols, IECs, and consultation with colleagues; and 4) in order to resolve them better, what they most demand are protocols and IECs, but also bioethics consultants. (shrink)