Some 26% of childhood deaths and 25% of the total disease burden in children under five were attributed to environmental exposures in 2012. This estimate indicates the potential burden of disease that could be prevented by environmental interventions. The disease burden from environmental risks based on these calculations is especially large in children under five years of age and is largely composed of infectious and parasitic diseases and neonatal and nutritional conditions. In children 5 to 15 years old, injuries and noncommunicable diseases become relatively more important. The largest contributors to environmental DALYs in children under five years are respiratory infections, followed by diarrhoeal diseases and neonatal conditions. The bulk of the disease burden in children attributable to the environment occurs in low- and middle income countries. Many adverse environmental exposures such as to chemicals during childhood lead to disease or early death at adult age. Preventing these exposures during childhood could therefore contribute importantly to reducing the growing worldwide numbers of diabetes, cardiovascular diseases and cancer. Effective preventive interventions exist that protect children from adverse environmental exposures, many of which are listed in this report. A strong focus on primary prevention through reducing environmental risks will not only improve children’s health but also lead to healthcare savings. The environment is a key element of protecting children’s health and reducing health inequalities. Intersectoral action such as between the health, energy, transport, industry/ commerce, housing and water sectors will be required to appropriately reduce environmental risks. Interventions that reduce environmental risks have the potential to greatly contribute to achieving the Sustainable Development Goals and these interventions generally benefit health, the climate, the environment and overall development at the same time.