In this talk I will focus on the production and disputation of facts in knowledge infrastructures. I suggest that the way matters of fact are made, confirmed, certified, contested or rejected, provides insight into imaginaries, moral worlds and the kinds of accountabilities important for the making and retaining of a tolerable level of security and certainty in human affairs. Five questions will be debated: How far do designed and emerging futures depend on the modes of evidence making? How can modes of evidence making deal with multiple and contradicting ontologies? In what way are standards of accountability and responsibility dependent on evidence making? Is evidence making intertwined with precaution, thoughtfulness, acting wisely, concern and care? What are the conditions of possibility to “speak truth to power”?