Pneumonia is one of the most common global childhood illnesses. The diagnosis relies on a combination of clinical judgement and radiological and laboratory investigations. Streptococcus pneumoniae remains the most important cause of childhood community-acquired pneumonia. In addition, viruses (including respiratory syncytial virus) and atypical bacteria (Mycoplasma and Chlamydia) are likely pathogens in younger and older children in developed countries. In the minority of cases only, the actual organism is isolated to guide treatment. Antibiotics effective against the expected bacterial pathogens should be instituted where necessary. The route and duration of antibiotic therapy, the role of emerging pathogens and the impact of pneumococcal resistance and conjugate pneumococcal vaccines are also discussed.