The highest stage in the history of the labor movement came with the unionization of the Fordist-Taylorist factory system.The concept of the “Fordist-Taylorist factory system,” first developed in Antonio Gramsci, “Americanism and Fordism,” in Selections from the Prison Notebooks (New York: International Publishers, 1971), 277–318, was popularized in the 1970s by France's “regulation economists” (Boyer, Aglietta, Lipietz, Coriat). It refers to those mass-production metal-fabrication plants based on the assembly-line techniques devised by Henry Ford and managed according to the “scientific” principles worked out by Frederick Winslow Taylor. The U.S. auto industry of the 1920s and 1930s best exemplifies this form of production. Neither before nor since has labor achieved a comparable influence. In the United States and France, this stage was reached in the same period and through roughly similar means. In June 1936, a massive wave of factory occupations swept across the Paris metal industry, forcing employers to introduce one of the world's most progressive systems of industrial relations. Six months later, sit-in strikes in Flint, Michigan, defeated the open shop at the General Motors Corporation, opening the way to the subsequent unionization of America's mass-production sector. These two events, the dominant peaks in the history of the modern labor movement, have rarely been viewed in the same light, yet they were part of a unique set of circumstances affecting not merely the fate of unionism, but that of industrial society.Most accounts of the French and American occupations make reference to the other national case, but the only actual attempt to compare them is to be found in Sidney Fine, Sit-Down: The General Motors Strike of 1936–1937 (Ann Arbor: University of Michigan Press, 1969), 125–8. Notwithstanding his definitive study of the Flint occupations, Fine's treatment of the Paris strikes, based on a few English language sources, examines only their general contours, not the structural and contingent factors linking them with the Flint movement. Cf. Val R. Lorwin, “Reflections on the History of the French and American Labor Movements,” The Journal of Economic History, 17 (March 1957).