Since the introduction of the principle of respect of autonomy in medical ethics, the respect of the will of the patient occupied a central place in the decision-making process. To face up to the difficulties that appeared during the application of this principle in clinical medicine, Bruce Miller proposed in the early eighties one way to clarify the significance of this notion in the field of medical practice. He showed that the concept of autonomy can be understood under four senses which deserve to be explored in case of ethical conflict. This article shows, through the analysis of a clinical situation, the relevance of the approach suggested by this author and proposes to refer to this approach in case of ethical dilemmas in clinical practice.