'Tackling some of the most pressing issues facing the public on the effect of social media on democracy, Persily and Tucker and contributing authors provide a grand tour of what academic research has taught us about digital politics and policy. From hate speech to polarization to misinformation and beyond, this work elucidates what we know about the impact of the Internet on democracy and presses us to think critically about how we can move this body of work forward to best inform policymaking. Social Media and Democracy should be required reading - for policymakers, academics, researchers, students of digital politics, and the general public.' Margaret Roberts, University of California, San Diego