Prevention in public policy is much discussed but rarely theorized. This article begins with a theoretical framework for reflecting on the political economy of prevention in advanced capitalist economies that integrates the analysis of preventive policies across the social, environmental and economic domains. The next two sections survey prevention initiatives in social policy and climate change policy, respectively. These mainly focus on the last three decades and are based mainly on UK evidence. The article then considers the relative absence of prevention in contemporary economic policy and management: today's neo-liberal economic and political order powerfully constrains preventive public policy. The final section outlines an alternative social political economy that prioritizes preventive and precautionary policy making.