Environmental determinants of health are responsible for more than a quarter of the burden of disease in the Western Pacific Region. Communicable and noncommunicable disease, disability and death result from a lack of safe water and sanitation, indoor and outdoor air pollution, hazardous chemicals, occupational hazards and climate-related disasters. The Western Pacific Regional Framework for Action on Health and Environment on a Changing Planet intends to relaunch the World Health Organization (WHO)'s Health and the Environment program and fulfill its mandate in the area of environmental health. It proposes to leverage the health sector focus on the Sustainable Development Goals (SDGs) process, providing guidance for prioritizing the work of WHO in support of Member States improving health outcomes through action on environmental determinants. It articulates entry points for health and environment priority actions in WHO country cooperation strategies, the United Nations Framework Convention on Climate Change and other mechanisms for international collaboration, and notably with the United Nations Environment Program and ministries of environment. The framework also sets a course for the health sector to advocate adaptive measures, policies and action to protect health and well-being as a co-benefit of interventions in energy, agriculture, transport, housing and other spheres.