Despite policies and action plans put in place by countries at a global level, overweight continues to be a pressing public health issue and one of the key drivers of non-communicable diseases in OECD countries and beyond. This chapter brings together the main messages of this publication and describes the key policy implications from new OECD analyses on the health, social and economic burden of being overweight and its associated lifestyles, including poor diet, lack of physical activity and sedentary behaviour. The chapter presents trends and projections for up to 52 OECD (including accession and partner countries), Group of 20 (G20) and European Union (EU28) countries and makes a strong economic case for upscaling investment in policies that promote healthy lifestyles. The chapter concludes by presenting the expected effectiveness, impact on health expenditure and return of investment for ten such policies and analyses the potential implementation costs and approaches to mitigating such costs.