How can we account for the role of ignorance and knowledge in global governance? It is a contention of earlier scholarship in international relations and political sociology that knowledge production is tightly coupled with rational action – regardless of whether knowledge widely influences different stakeholders or not. This scholarship equally tends to assume an ignorance-knowledge binary relationship that associates ignorance with powerlessness and knowledge with power. This is a view we dispute. Calling for a new approach to the study of ignorance and knowledge in international politics, our article builds on research from ignorance studies, science and technology studies and critical race theory to derive a novel typology of epistemologies of power in which truth and ignorance are defined and combined in a plurality of ways. Approaching differing epistemologies of power in the transnational realm in a general or 'ecumenical' manner, we identify weaknesses in earlier approaches to the study of knowledge production in global affairs, and present four new concepts: 'factual determinism', 'cynical realism', 'unseeing proceduralism' and 'hopeful constructivism'. Through this framework, our article calls for greater recognition of the constitutive role that ignorance plays in operations of power on a global scale.