With Obfuscation, Finn Brunton and Helen Nissenbaum mean to start a revolution. They are calling us not to the barricades but to our computers, offering us ways to fight today’s pervasive digital surveillance—the collection of our data by governments, corporations, advertisers, and hackers. To the toolkit of privacy protecting techniques and projects, they propose adding obfuscation: the deliberate use of ambiguous, confusing, or misleading information to interfere with surveillance and data collection projects. Brunton and Nissenbaum provide tools and a rationale for evasion, noncompliance, refusal, even sabotage—especially for average users, those of us not in a position to opt out or exert control over data about ourselves. Obfuscation will teach users to push back, software developers to keep their user data safe, and policy makers to gather data without misusing it.