Relations between workers and managers underwent a profound transformation in the early years of the twentieth century. Employers began a systematic attempt to control production and rationalize shop floor processes through technological innovation, subdivision of tasks, and the scientific management (or Taylorism) movement. A concern for a tractable labor force compelled the development of the profession of personnel management and “corporate welfare” work on the part of employers. The all-round skilled craftsman, trained by a union apprenticeship and able to work in any area of the trade without management instruction and supervision, was replaced by the semiskilled machine operative trained by the company to work on a few tasks using modified and specialized machinery. On the other side, craftsmen accustomed to autonomy in their work and governed by a collective ethic felt their organized power threatened by this management offensive that debased skill, imposed new forms of discipline, and promoted individualism and competition. Craftsmen challenged management's encroachment upon the shop floor through militant union action, but in doing so they were forced, by the “dilution” of their trade (the British term for the destruction of skilled jobs), to rethink their traditional reliance on exclusive craft knowledge. The key to any new strategy was the ability of craftsmen to transcend old craft lines, join with the less skilled workers whose jobs were created by management reorganization, and formulate new demands. The World War I years and the production crisis produced by the war saw the permanent institutionalization of the “new factory system” in the United States and elsewhere. The metal trades were the industrial sector most affected by management reorganization, and during the war years this sector was the most strike-prone (Nelson, 1975; Taylor, 1967; Braverman, 1974; Montgomery, 1974, 1976; Nadworny, 1955; Hinton, 1973; Bing, 1921).