Recent research suggests that musculoskeletal pain may be the most common complaint for which children are referred to a pediatric rheumatologist and is present in approximately 50% of all new patients. A small percentage of these patients will be diagnosed with a form of juvenile idiopathic arthritis (JIA), which is marked by clinically significant pain. A larger percentage will be diagnosed with a musculoskeletal pain syndrome, that approximately 25% of them are chronic and defined as > = 3 months. The chronic pain symptom is a subjective one that professionals have to precise its outlines in term of semiology, nature and efficacity of past treatments, medical and family backgrounds. The professional then will have to pinpoint a diagnosis, while assessing the consequences of the pain and treating it.