Explore the critical role of epidemiology in promoting healthy populations through this thought-provoking lecture by Sandro Galea, dean and Robert A. Knox Professor at Boston University School of Public Health. Delve into the causes and consequences of health epidemics, examining how our understanding of these factors impacts public health outcomes. Gain insights into the challenges faced in domestic health policies, the misconceptions surrounding health causes, and the importance of environmental factors. Compare health systems between the US and Canada, and discover what truly matters in creating healthier communities. Engage with questions from the audience and learn how to apply epidemiological thinking to improve population health in this comprehensive presentation from the 2017-2018 Epidemics Science Lecture Series at Harvard University's Radcliffe Institute for Advanced Study.