Book excerpt: The Trump presidency has been one of the most eventful and controversial in American history, with consequences for the governance and policy of the US and beyond. While Trump left office claiming a long list of ‘Trump Administration Accomplishments’, his time in office was also marked by a hailstorm of criticism. But beyond the sensationalist tweets and news stories, what policy effects did he bring? This volume provides an extensive and authoritative set of studies evaluating Donald Trump’s impact on American society and beyond. It provides a new layered framework for assessing the policy impact of leaders, which can be used for understanding presidential and prime ministerial leadership more widely. Chapters explore his impact on American democracy, Congress, the Supreme Court, the economy, the COVID-19 pandemic, the environment, American soft power, the international system and more. The chapters in this book were originally published as a special issue of the journal Policy Studies.