[Chronic pain : from symptom to disease].

At last, chronic pain, with its consequences and impact for patients and society, is now considered as a disease in its own in the 11th revision of the international classification of diseases (ICD). We present here in the light of two clinical cases, why the diagnosis of chronic primary pain is useful and how to utilize these new codes. We hope to rapidly see the awaited impact on the healthcare system (from the patient care to insurance issues), as on research and teaching.