Patients with chronic disease are generally required to take long-term treatments to treat their illness and avoid complications. However lack of adherence is very common and represents major barriers to treatment efficiency. The objectives of this study are to evaluate the level of acceptance to medication in chronic diseases patients (Crohn’s disease, chronic obstructive pulmonary disease, Osteoarthritis) in real life; to identify issues and to define priorities for action. Treatment acceptance is not satisfactory in chronic disease patients. General acceptance is mainly driven by patients’ perceived treatment effectiveness, side effects and long term use while socio-demographical and clinical characteristics have a minor contribution. These findings indicate patients’ priorities and unmet needs; however, they must be confirmed using longitudinal data.