Résumé : In children, all ENT cavities are particularly prone to the development of chronic inflammation. This is due to many predisposing factors, of which the most common are unfavourable anatomy, absence of nasal blowing, day care attendance, allergy, immature immunity, gastro-oesophageal reflux and tobacco smoke exposure. The aim of this paper is to outline the most specific paediatric clinical aspects of chronic pharyngo-tonsillitis, rhinosinusitis, otitis media, adenoiditis and laryngotracheitis and the important influence that some of these pathologies exert on the others.