Book excerpt: Donald Trump’s presidency produced no end of controversy. His tumultuous presidency also created new avenues of public policy and national politics. Prominent scholars of American institutions, politics and public policy assess the multiple consequences of Trump’s singular presidency in this volume. How did Trump’s unconventional behavior alter the media environment and electoral politics? Will he remain the dominant presence in the Republican Party? Are Democrats the main beneficiaries of his time in office? How lasting was his impact on the federal judiciary, Congressional-executive relations and White House management? What new directions in domestic and foreign policy are likely to survive his presidency? The authors shed much light on the temporary and permanent changes to the policy and political landscape wrought by this argumentative and controversial chief executive.