One of the biggest challenges for doctors working in chronic care is the correct management of the argumentation phases during the encounters with their patients. During these phases doctors should provide patients with acceptable reasons for being adherent to treatment and for changing certain unhealthy behaviors and lifestyles, something which is particularly difficult for elderly patients, for whom changing life long habits can be extremely hard. However, the medical literature on the subject of communication in the chronic care encounter shows lack of theoretical models and methodological approaches that can highlight which specific linguistic structures or elements in different communication styles favor or impede patient commitment, trust in the relationship and adherence to treatment. The contribution describes ongoing research on argumentative strategies in the encounter with diabetes patients. I describe one recently concluded research project on the argumentation phases of medical encounters in diabetes care, which highlighted critical areas in need of improvement. I also describe the design and aims of a new research project, aimed at testing the effectiveness and usability of certain argumentation schemes in the medical encounter.