This collection of thirteen new essays is the first to examine, from a range of disciplinary perspectives, how the new technologies and global reach of the Internet are changing the theory and practice of free speech. The rapid expansion of online communication, as well as the changing roles of government and private organizations in monitoring and regulating the digital world, give rise to new questions, including: How do philosophical defenses of the right to freedom of expression, developed in the age of the town square and the printing press, apply in the digital age? Should search engines be covered by free speech principles? How should international conflicts over online speech regulations be resolved? Is there a right to be forgotten that is at odds with the right to free speech? How has the Internet facilitated new speech-based harms such as cyber-stalking, twitter-trolling, and revenge porn, and how should these harms be addressed? The contributors to this groundbreaking volume include philosophers, legal theorists, political scientists, communications scholars, public policy makers, and activists.