For the purposes of this study, violence is defined as the "nonprivileged physical interference with the person or property of another, or the threat, express or implied, of such interference." Data on labor violence were obtained from case files of the National Labor Relations Board (NLRB), incident summaries from an ongoing but recent data base maintained by the National Right to Work Legal Defense Foundation, press reports, personal interviews, and field studies. This study assesses the incidence, motivations, and common tactics of union violence, paying special attention to the organizations most often involved in violent strikes or organizational drives; these include the United Mine Workers, the Teamsters and other transportation unions, construction organizations, and public service employees. The study analyzes the use and effectiveness of various legal remedies, including the Norris-laGuardia Anti-Injunction Act, the Anti-Racketeering (Hobbs) Act, the National Labor Relations (Taft-Hartley) Act, and State and Federal criminal laws. Recommendations for changes in these laws are proposed. The study concludes that there is a leniency toward union violence in the United States. The proposed reforms are designed to increase the expression of social disapproval of such conduct, prevent violence, and provide improved relief to its victims. For a section on violence by public safety unions, see NCJ-123939. Chapter notes and tables, subject index, case index.