From anti-war walkouts to anarchist youth newspapers, rallies against educational privatization, and workshops on fair trade, teenage girls are active participants and leaders in a variety of social movements. Rebel Girls: Youth Activism and Social Change across the Americas illuminates the experiences and perspectives of these uniquely positioned agents of social change. Jessica K. Taft introduces readers to a diverse and vibrant transnational community of teenage girl activists in the San Francisco Bay Area, Mexico City, Caracas, Buenos Aires, and Vancouver. Expansive in scope and full of rich details, Taft brings to life the voices of these inspiring activists who are engaged in innovative and effective organizing for global and local social justice, highlighting their important contributions to contemporary social movements and social theory. Rebel Girls explores how teenage girls construct activist identities, rejecting and redefining girlhood and claiming political authority for youth in the process. Taft examines the girl activists’ social movement strategies and collective political practices, detailing their shared commitments to process-based political education, participatory democracy, and hopeful enthusiasm. Ultimately, Rebel Girls has substantial implications for social movements and youth organizations, arguing that adult social movements could learn a great deal from girl activists and making clear the importance of increased collaboration between young people and adults.