When the Gates Foundation determines which diseases count as global priorities, when Bloomberg Philanthropies reshapes urban governance worldwide, and when the Chan Zuckerberg Initiative reorganizes public education and biomedical research, billionaire philanthropies do more than give money—they exercise governing power. In an era of unprecedented wealth concentration and inequality, billionaires have emerged as powerful political actors, taking on roles once played by states and multilateral organizations. These wealthy individuals and their foundations now finance the provision of global public goods, and are self-conscious about wanting to shape public policy, democratic politics, and international development. Even as these actors assume roles historically associated with governments and multilateral institutions, they operate outside the norms of democratic accountability. This course will explore how philanthropic actors produce knowledge, set agendas, and introduce new norms and practices that blur the boundaries between public and private. It will draw on a range of case studies: how charter schools became the mainstay of education reform in the US; what drives a “new green revolution” in Africa; how polio eradication became the overwhelming priority of many global health institutions; how think tanks that work on AI ethics and governance are bankrolled; how social movement organization in California’s Central Valley and disaster management in New Orleans are shaped by powerful philanthropic actors. Students will collectively work on these case studies, using them to assess the implications for democracy, accountability, and social justice in a world increasingly governed by private wealth.