In recent years, the debate about the role of digital technology in our society, our economy and our democracies has shifted, and questions about the social and economic costs of the platform economy have emerged. Democratic governments around the world have begun to search for a strategy to govern the digital public sphere. Many are converging on what might be called a platform governance agenda. But what might a platform governance agenda look like? This paper considers three dimensions. The widespread adoption of digital technology over the past 20 years into virtually all aspects of our lives has been tremendously empowering and has led to some real social progress. But we are now also seeing the costs. As the technology evolution barrels forward, and as we enter a world of human-digital augmentation, biotechnology, artificial intelligence and the Internet of Things, we need to make sure we have a governance system that is capable of both minimizing the inevitable social costs and holding these new institutions of power democratically accountable.