Nearly all global mortality in children younger than 5 years (99%) occurs in developing countries. The leading causes of mortality in children younger than 5 years worldwide, pneumonia and diarrhoeal illness, account for 1•396 and 0•801 million annual deaths, respectively. Although important advances in prevention are being made, advanced life support management in children in developing countries is often incomplete because of limited resources. Existing advanced life support management guidelines for children in limited-resource settings are mainly empirical, rather than evidence-based, written for the hospital setting, not standardised with a systematic approach to patient assessment and categorisation of illness, and taught in current paediatric advanced life support training courses from the perspective of full-resource settings. In this Review, we focus on extension of higher quality emergency and critical care services to children in developing countries. When integrated into existing primary care programmes, simple inexpensive advanced life support management can improve child survival worldwide.