Gastroenteritis in children is still a common reason for consulting a general practitioner and for hospital admission. Rotavirus is the most common cause of gastroenteritis in children and accounts for half of all hospital admissions for severe acute infectious diarrhoea. Most children with gastroenteritis do not develop dehydration and can be treated at home. Children with mild to moderate dehydration should be treated with low osmolarity oral rehydration solutions, and those with severe dehydration or shock need to be admitted for administration of intravenous fluids. Lactose-free feeds should not be routinely used after acute gastroenteritis, but there is some evidence that a lactose-free diet may reduce the duration of diarrhoea. Antimotility drugs are rarely indicated in children with gastroenteritis, as the potential risks outweigh the benefits. The development of a rotavirus vaccine would provide huge public health benefits and cost savings. Other preventive strategies include educating people about personal and food hygiene and encouraging breastfeeding.