Book excerpt: Protest Politics in the Marketplace examines how social media has revolutionized the use and effectiveness of consumer activism. In her groundbreaking book, Caroline Heldman emphasizes that consumer activism is a democratizing force that improves political participation, self-governance, and the accountability of corporations and the government. She also investigates the use of these tactics by conservatives. Heldman analyzes the democratic implications of boycotting, socially responsible investing, social media campaigns, and direct consumer actions, highlighting the ways in which such consumer activism serves as a countervailing force against corporate power in politics. In Protest Politics in the Marketplace, she blends democratic theory with data, historical analysis, and coverage of consumer campaigns for civil rights, environmental conservation, animal rights, gender justice, LGBT rights, and other causes. Using an inter-disciplinary approach applicable to political theorists and sociologists, Americanists, and scholars of business, the environment, and social movements, Heldman considers activism in the marketplace from the Boston Tea Party to the present. In doing so, she provides readers with a clearer understanding of the new, permanent environment of consumer activism in which they operate.