Truth and power have a difficult relationship. Decision makers are often required to make judgements that depend upon specialized knowledge and thus reluctantly surrender power. They are apt to reject advice inconsistent with their perceived interests, experiences and cognitive capacities. Speaking Truth to Power aims to guide the reader through the tangled relationship between truth and power, manifesting as the interplay between experts and decision-makers in society. Through a combination of careful observation and original analysis, the authors draw out the incentives and tensions that drive the relationship between these actors. They review some of the history of expertise, consider the values of experts and decision-makers, and analyze what has succeeded and what has failed as truth and power have worked together and against one another, primarily in the U.S. but also drawing on international examples. Policymaking professionals, academic experts interested in evidence-based policymaking and graduate and undergraduate students in public policy, government, or political science will value this assessment of truth and power.