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Most social media users want their chosen platforms free from harassment and porn. But they also want to see the content they choose to see. This means platforms face an irreconcilable contradiction: while platforms promise an open space for participation and community, every one of them imposes rules of some kind.

In the early days of social media, content moderation was hidden away, even disavowed. But the illusion of the open platform has, in recent years, begun to crumble. Today, content moderation has never been more important, or more controversial. In Custodians of the Internet, Tarleton Gillespie investigates how social media platforms police what we post online – and the societal impact of these decisions.

“I have been writing about the impact of platforms and the digital transformation for fifteen years,” said Gillespie. “This book explains how content moderation works: how the platforms think of their responsibilities, the way they create and articulate the rules, the labor behind the scenes, and recent efforts to automate it all.” Based on interviews with content moderators, creators, and consumers, this book contributes to the current debates about the public responsibilities of platforms, be it about harassment, data privacy, or political propaganda.

Gillespie argues that content moderation still receives too little public scrutiny. How and why platforms moderate can shape societal norms and alter the contours of public discourse, cultural production, and the fabric of society.


published by Yale University Press, June 2018



How social networks set the limits of what we can say online. Wired June 26, 2018 (includes material excerpted from Chapter 2)

Improving moderation. July 17, 2018. (expanded section from Chapter 8)


Praise for the book:

“Online platforms are defining our technological landscape, shaping our lives online and off. Custodians of the Internet is the exquisitely-drawn map that shows us how they do it.”— Jonathan Zittrain, author of The Future of the internet and How to Stop It, and director of the Berkman Klein Center for Intern & Society at Harvard University

“In this timely and important book, Gillespie deftly reveals the factors that shape social media platforms, and thus our world. Clear-eyed and incisive, a must-read for anyone interested in the influence of platforms, the forces that structure this influence, and crucially how to move forward.”— Zeynep Tufekci, contributing opinion writer for The New York Times and author of Twitter and Tear Gas

"Truly stellar. Gillespie’s analysis deftly contextualizes moderation policies on social media platforms, and illuminates how the platforms' underlying values are baked into these policies. The result is essential reading."— Whitney M. Phillips, author of This Is Why We Can't Have Nice Things: Mapping the Relationship between Online Trolling and Mainstream Culture

"In this lively and entertaining book, Tarleton Gillespie shows us how social media regulate our speech in many different ways, some overt and some hidden. He explains why content moderation is not a peripheral function of social media, but central to their very existence."— Jack Balkin, founder of the Information Society Project at Yale Law School

“No one knows how digital platforms are shaping our lives better than Tarleton Gillespie. This book is an essential guide to the social and technical processes that animate our new media – and to the principles by which we might put them to more democratic ends.”— Fred Turner, author of From Counterculture to Cyberculture and The Democratic Surround



About the Author

Tarleton Gillespie is a principal researcher at Microsoft Research New England, and an affiliated associate professor at Cornell University in the Department of Communication and the Department of Information Science. He cofounded the blog Culture Digitally. His previous book is the award-winning Wired Shut: Copyright and the Shape of Digital Culture (MIT 2007). He also co-edited Media Technologies: Essays on Communication, Materiality, and Society (MIT 2014)

His research has appeared in New Media & Society; Social Media & Society; The International Journal of Communication; Information, Communication, & Society; The Information Society; Limn; and Social Studies of Science. His writing has appeared in Wired, Salon, the Neiman Journalism Lab, and The Atlantic online, and he has been quoted in Wired, The Washington Post, The Wall Street Journal, Quartz, BBC Radio, and NPR.

Gillespie