Osteo-articular symptoms are frequent in pediatrics, but chronic arthritis is rare in childhood. Arthritis may be difficult to recognize in children and there is a large differential diagnosis including infectious and neoplastic diseases. Even if juvenile arthritis has often a favourable course, significant functional damage may occur. The diagnosis and the follow-up of chronic arthritis should be performed in collaboration with a specialized consultation in pediatric rheumatology, in order to allow access to multidisciplinary medical care and help to increase the clinical and epidemiological knowledge in these rare diseases. A study is starting this fall aimed at collecting epidemiological datas on childhood arthritis in the french part of Switzerland.