Confidentiality is both a fundamental principle of medical ethics and a legal obligation. In exceptional situations not covered by legal provisions, doctors may want to waive confidentiality against the wishes of the patient. Swiss law calls for an authority to rule on such cases. In the Canton of Geneva this authority is the Commission for Professional Confidentiality. This paper concerns 41 cases managed by this commission. The study shows that the majority of these requests to the Commission concern the reporting of patients who are not incompetent but need the protection of a legal guardianship. In rare cases, there is another interest higher than confidentiality: public order or functioning of justice. The Commission found that the measure requested was justified in the majority of cases brought before it. This study focuses on exceptional cases but it throws into relief the conflict between the principle of autonomy on the one hand and the need for patient protection and social justice on the other.