A groundbreaking labor study, this book offers a detailed portrait of the Citizens Alliance (CA), a union of Minneapolis business owners, which employed any means necessary to squelch the power of organized labor. The association blacklisted union workers, ran a spy network to ferret out union activity, and, when necessary, raised a private army to crush its opposition with brute force. The influence of the CA also reached across the state to battle socialists, labor unions, the Nonpartisan League, and the Industrial Workers of the World. The book examines the philosophies and tactics of the Citizens Alliance from its inception in 1903 to the passage of the Labor Management Relations Act of 1947, legislation that effectively inhibited the power of unions. Based on over ten years of meticulous archival research, this book delves into such subjects as the founding of the William Hood Dunwoody Industrial Institute; the 1917 Streetcar Strike and the 1934 Teamsters' Strike; and the CA's collaboration with the Commission of Public Safety, Northwest Bancorporation, the courts, and the military. Both a business history and a labor history, A Union Against Unions offers a comprehensive picture of the CA's campaign against organized labor and a fascinating view of Minnesota history during the first half of the twentieth century.