Lower respiratory tract infections (LRTI) encompass a wide range of clinical syndromes, prominently including bronchiolitis, bronchitis and pneumonia. LRTIs are the second leading cause of antibiotic prescriptions. The vast majority of these infections are due to (or triggered by) viruses and are self-limited diseases. Pneumonia in children is responsible for significant morbidity and mortality worldwide. For clinicians, one of the main difficulties consists in diagnosing pneumonia in febrile children with (or without) cough. The diagnosis is given on the basis of anamnesis, clinical examination and (if necessary) complementary examinations, with chest X-ray or thoracic ultrasound; biological markers are particularly important. Over recent years, since the implementation of PCV13, the bacterial epidemiology of pneumonia and empyema has evolved; involvement in these diseases of pneumococcus has been reduced, and resistance to penicillin has lessened - and remained extremely low. In 2021, according to the National Pneumococcal Reference Center, only 6% of the strains isolated from blood cultures in children are resistant to amoxicillin. The therapeutic choices proposed in this article are in full compliance with the previously published official French recommendations.