This lecture described the role that scientific evidence has in the establishment of governance and in its maintenance, and will also present findings from the International Tobacco Control Policy Evaluation Project, the first international research project to evaluate the effectiveness of FCTC policies, including examples of how ITC findings have contributed to the formation and implementation of strong, evidence-based tobacco control policies throughout the world. The lecture will also provide a summary of ITC findings about the impact of tobacco control policies such warning labels and smoke-free laws, including similarities and differences of policy impact between high-income and low- and middle-income countries.