The Global Financial Crisis of 2008 and the Great Recession that ensued had reverberations that were not only social, political and economic. The crises also led to increased doubt in the value and usefulness of policy expertise and in its producers. This ‘epistemic crisis’ is the starting point of this thematic issue dedicated to think tanks in the aftermath of the Global Financial Crisis and Great Recession. The Introduction to the issue has four objectives. First, it gives a high-level overview of the challenges and opportunities think tanks have faced in the wake of these crises, given the paradox of growing demand for policy expertise precisely at the moment when such expertise and its makers became suspect for many. Second, the Introduction gives an overview of the research literature on think tanks and their role in the policy-making process and the public debate. Third, the articles comprising this thematic issue are introduced, and connections between them established. Fourth, the introduction gauges the effects of Global Financial Crisis and Great Recession, but also crises more generally, on think tanks and the environment they operate in, and speculates about the future of the think tank industry.