A sit-down strike (or simply sitdown) is a labour strike and a form of civil disobedience in which an organized group of workers, usually employed at factories or other centralized locations, take unauthorized or illegal possession of the workplace by "sitting down" at their stations.^[1] By taking control of their workplaces, workers engaged in a sit-down demonstrate their power, build solidarity among themselves, prevent the deployment of strikebreakers or removal of industrial equipment, and cause cascading effects on the chain of production within and between factories. However, sit-down strikes are illegal in the vast majority of countries, complicating their use.

Sitdown strikes played a central role in the unionization of manufacturing in the United States and France. In major strikes in the rubber and automotive industries in the United States, labor organizers with the United Rubber Workers of America and United Automobile Workers adopted the sitdown strike as a means for demanding unionization of factories, achieving major successes at Goodyear Tire (1936), General Motors (1936-37), and Chrysler (1937).^[2] Sit-down strikes peaked in the United States in 1937, and rapidly declined as workers began to face criminal prosecution for occupations while the National Labor Relations Board supervised both unionization elections and collective bargaining by between recognized unions and employers. While some sit-down strikes still occur in the United States, they tend to be spontaneous and short-lived.

A wave of sit-down strikes in France in May to August 1936 demanded and won union recognition and industry-wide negotiations on wages and benefits, and coincided with state guarantees of limited hours, vacation pay, and other social reforms.

Author Louis Adamic, in his account of the late 1930s wave of sit-down strikes in the United States wrote the following definition in the fall of 1936:

SITDOWN, n. Act of quitting work in one or a few departments of a delicately organized mass-production factory with the aim of stopping operations in the entire or most of the plant; specif. such an act done by mutual agreement by workers in one or a few departments of such a factory as a means of enforcing compliance with demands made upone their employers; sudden strike workers in one or a few departments of such a factor, decided upon and called by themselves while on the job, usually without the sanction of any recognized labor-union leader or official and, as a rule, of short duration, the strikers and the rest of the workers remaining idle (sitting down) by their machines or belt conveyors pending the compliance with their (the strikers') demands. See STAY-IN and QUICKY.^[3]

Ahmed White distinguishes three types of sit-in strikes: "short, 'quickie' strikes, characterized by brief, on-the-job work stoppages," like those described by Adamic; "the classic 'stay-in' strike", defined "a work stoppage in which the strikers occupied the workplace to prevent the employer from using it for a considerable period of time"; and "'skippy' strikes, characterized by intentionally sloppy performance on the production line."^[4] Sit-down strikes also built upon the tactics, used by the Industrial Workers of the World, of the "folded arms strike" and "striking on the job" (which, according to Adamic, "required men to pretend they were working, and to accomplish as little as possible without being discharged").^[5]

In factories built around assembly lines, sit-down strikes enabled small numbers of workers to interrupt production across an entire plant. In industries with complex chains of production, such as automobile manufacturing, it likewise projected power outward from a factory on strike: "just as a militant minority could stop production in an entire plant, so if the plant was a key link in an integrated corporate empire, its occupation could paralyze the corporation."^[6] Adamic describes the sit-down strike as educating workers about their power as well as providing an opportunity to organize non-union workers: "And sitting by their machines, caldrons, boilers, and work benches, they talked. Some realized for the first time how important they were in the process of rubber production. Twelve men had practically stopped the works! … The active [i.e., pro-union] rank-and-filers, scattered through the various sections of the plant, took the initiative in saying, 'We've got to stick with 'em!' And they stuck with them, union and non-union men alike."^[7] White describes this process as "an extraordinary forum for cultivating loyalty and solidarity among workers, offering rank-and-file workers a salient symbol of the union's ability to confront the employer, as well as numerous occasions for the actual practice of mutual support."^[8]

When feasible, sit-down strikes offered numerous stategic and tactical advantages. Adamic observed in the 1930s that "[Quickie] sitdowns are quick, short, and free of violence." The tactic prevents employers from replacing them with strikebreakers or removing equipment to transfer production to other locations. Neal Ascherson has commented that an additional attraction is that it emphasizes the role of workers in providing for the people and allows workers to in effect hold valuable machinery hostage as a bargaining chip.^[9] Other advantages listed by Adamic include:

• Sitdown strikes happen inside factories, where workers have the advantage of familiarity and knowledge of the space. This contrasts with the tactical advantages that police and private security have in outdoor picket lines.
• While many workers are morally opposed to sabotage, "The sitdown is the opposite of sabotage… It destroys nothing."^[10]
• By stopping work but keeping workers in a single space, the sitdown strike generates a new and enjoyable social space for hundreds or thousands of workers: "The sitdown is a social affair. Sitting workers talk. They get acquainted. And they like that."^[11]

Labor strategists who recognized the value of the sit-down strike include Dutch Council Communist Anton Pannekoek,^[12] American labor historian Jeremy Brecher,^[13] and sociologist Beverly Silver.^[14]

In describing the origins of the sitdown strike, scholars, workers, and politicians have pointed to construction strikes at the pyramids of ancient Egypt and medieval European cathedrals.^[15][16] Strikes by crews aboard merchant ships, which peaked in the eighteenth century "were (and remain) like sit-down strikes by their very nature" and spread to the rest of the maritime industry.^[16] Early twentieth-century stoppages were recorded in the French, Argentine, and United States rail industry.^[17]

In September 1920, the Federation of Italian Metal Workers led a wave of strikes over wages, eventually involving nearly five hundred thousand workers, and featuring numerous factory occupations. During the struggle, workers began operating some factories under their own control and Communist factory workers demanded control of the industry itself by workers' councils.^[16] Workers staged strikes that occupied mines in Greece, Yugoslavia, Hungary, Poland, Spain, France, England, and Wales from 1934 to 1936.^[15][18] These included a successful strike in Carniola in July 1934.^[11] A major sitdown strike occurred on March 22, 1936 at Krakow's Semperit rubber works, during which violence claimed the lives of six people.^[11]

Labor historian Michael Torigian argues that the use of sit-down strikes and factory occupations by labor organizers in the United States and France in the 1930s marked an important shift in the role of the sitdown strike. In the United States and France, the sitdown strikes became "an aspect of the evolving labor movement as it pursued union goals within the context of the Fordist-Taylorist factory system", specifically the creation of industry-wide unions like the United Auto Workers. As a tool for industry and even nationwide unionization, Torigian concludes, sit-down strikes "took on a significance, a character, and an effect quite unlike anything that had previously occurred."^[19]

The sit-down strike was the inspiration for the sit-in, where an organized group of protesters would occupy an area in which they are not wanted by sitting and refuse to leave until their demands are met. Sidney Fine cites the protest form as being echoed and replicated in both the lunch counter sit-ins of the African American civil rights movement of the 1950s and 1960s, and in the university occupations of the 1960s.^[52]

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• Pen-down strike