Governments of all scales increasingly rely on data to form, implement, and evaluate policies, and to seek more effective ways to collect, utilize and disseminate data for better governance and societal engagements. The "Effective Policy Learning" column features engaging articles that highlight current developments in data science as well as efforts made in government sector around the world to uncover insights for evidence-based policy making. The aim is to equip policy makers with better understanding of the power and perils of data science, and to inspire data scientists to consider the public sector as a vital place to employ their skills and to maximize their impact.