Viral bronchiolitis is the commonest cause of hospital admission in young infants. Respiratory syncytial virus is responsible for most cases of bronchiolitis. Secondary bacterial infection is rare and antibiotics are seldom necessary. Most children with bronchiolitis develop only mild illness and can be managed at home. Infants born prematurely, those with pre-existing cardiac or respiratory disease, and infants in the first three months of life are more likely to need hospital admission. On current evidence, nebulised adrenaline, inhaled and systemic corticosteroids, and inhaled bronchodilators do not have a role in the routine management of infants with bronchiolitis.