Much of what is currently known about the adverse effects of ambient air pollution comes from studies conducted in high-income regions, especially North America and Europe, with relatively low air pollution levels. More recently, studies of long-term ambient air pollution exposure and its effect on morbidity and mortality in low- and middle-income countries have emerged. A new HEI-funded study by George Downward and Roel Vermeulen from Utrecht University, the Netherlands, addresses a clear research gap by leveraging harmonized data from the Asia Cohort Consortium, a large multicenter collaborative research effort in Asia that began in 2008. The study assessed the association between long-term exposure to ambient air pollution and mortality in more than 340,000 people in six Asian cohorts. The investigators estimated exposure for fine particles and nitrogen dioxide by using existing global satellite-based models and building on the exposure methods that are also used in the Global Burden of Disease project. In its independent review of the study, the HEI Review Committee thought this report adds to the overall knowledge base on health outcomes associated with air pollution in Asia. The large sample size and leverage of harmonized data (including lifestyle factors) from the Asia Cohort Consortium were considered to be strengths of the study.