This paper discusses the value of argumentation as an instrument for rational persuasion in doctor-patient (and general health professional–patient) communication. Argumentation can be used to influence those beliefs that form the basis of an individual's attitudes and decision-making process. In the medical context, argumentation can be used to legitimize the points of view of the doctor and the patient; to correct, add to, or modify a patient's set of beliefs; and to enhance the patient's central processing of the information that is foundational to his or her decision making. Overall, argumentation as a method of rational persuasion is an important communication tool for establishing conditions that are conducive to a patient's autonomous decision making. In this article, the issue of argumentation as rational persuasion is set within the context of several key topics in the area of health communication, namely, autonomy, the ways that doctors and patients interact and share information, and the effectiveness of information dissemination through traditional and new channels. Also, the difficulties of using argumentation effectively in this field are discussed, and areas of interest for future argumentation theory–based studies focused on enhancing its quality are highlighted.