Countries in the World Health Organization (WHO) South-East Asia Region are particularly vulnerable to a changing climate. Changes in extreme weather events, undernutrition and the spread of infectious diseases are projected to increase the number of deaths due to climate change by 2030, indicating the need to strengthen activities for adaptation and mitigation. With support from the WHO Regional Office for South-East Asia and others, countries have started to include climate change as a key consideration in their national public health policies. Further efforts are needed to develop evidence-based responses; garner the necessary support from partner ministries; and access funding for activities related to health and climate change. National action plans for climate change generally identify health as one of their priorities; however, limited information is available on implementation processes, including which ministries and departments would be involved; the time frame; stakeholder responsibilities; and how the projects would be financed. While progress is being made, efforts are needed to increase the capacity of health systems to manage the health risks of climate change in South-East Asia, if population health is to be protected and strengthened while addressing changing weather and climate patterns. Enhancing the resilience of health systems is key to ensuring a sustainable path to improved planetary and population health.