This is a pocket-sized manual for use by doctors, senior nurses and other senior health workers who are responsible for the care of young children at the first referral level in developing countries. It presents up-to-date clinical guidelines which are based on a review of the available published evidence by subject experts, for both inpatient and outpatient care in small hospitals where basic laboratory facilities and essential drugs and inexpensive medicines are available. It focuses on the inpatient management of the major causes of childhood mortality, such as pneumonia, diarrhoea, severe malnutrition, malaria, meningitis, measles, HIV infection and related conditions. It covers neonatal problems and surgical conditions of children which can be managed in small hospitals. This pocket book is part of a series of documents and tools that support the Integrated Management of Childhood Illness (IMCI).