In 2007, readers of the British Medical Journal voted that the introduction of clean water and sewerage- the 'sanitation revolution' of the Victorian era-was the most important medical milestone since the 1840s, over anaesthesia, antibiotics, or vaccines. These improvements led to a dramatic reduction in morbidity and mortality associated with faecal-oral infections, such as typhoid fever and cholera. Today, water, sanitation and hygiene (WSH) measures remain critically important to global public health, especially among children in lower income countries, who are at greatest risk from enteric infections and their associated symptoms, complications and sequelae. In this article, we review the evidence linking WSH measures to faecal-oral diseases in children. Although continued research is needed, existing evidence from the last 150 years supports extending life-saving WSH measures to at-risk populations worldwide. One recent estimate held that 95% of diarrhoeal deaths in children under 5 years of age could be prevented by 2025, at a cost of US$6.715 billion, through targeted scale-up of proven, costeffective, life-saving interventions. These include access to safe and accessible excreta disposal, support for basic hygiene practices such as hand washing with soap, and provision of a safe and reliable water supply. We present estimates of the burden of WSH-related disease followed by brief overviews of water, sanitation and hygiene-related transmission routes and control measures.i We conclude with a summary of current international targets and progress.