Advances in immunisation, improvements in socioeconomic status and effective HIV prevention and treatment strategies have reduced the population burden of childhood pneumonia and severe disease. However, pneumonia remains the major single cause of death in children outside the neonatal period, causing approximately 1 million deaths annually, or 15% of an estimated 6.3 million deaths in children aged under 5 years. This burden is disproportionately high in low- and middle-income countries and in Africa, where almost 50% of deaths in children aged under 5 years occur, despite African children comprising only 25% of live births globally. Pneumonia incidence and severity are highest in the first year of life, especially in the first 6 months.