"This report offers a high-level, evidence-informed guide to some of the major proposals for how democratic governments, platforms, and others can counter disinformation. It distills core insights from empirical research and real-world data on ten diverse kinds of policy interventions, including fact-checking, foreign sanctions, algorithmic adjustments, and counter-messaging campaigns. For each case study, we aim to give policymakers an informed sense of the prospects for success—bridging the gap between the mostly meager scientific understanding and the perceived need to act. This means answering three core questions: How much is known about an intervention? How effective does the intervention seem, given current knowledge? And how easy is it to implement at scale?" (Summary, page 1)