A study examined the relationship between high-performance workplace practices and the performance of plants in the following manufacturing industries: steel, apparel, and medical electronic instruments and imaging. The multilevel research methodology combined the following data collection activities: (1) site visits; (2) collection of plant performance data; (3) extensive interviews with managers and union officials; and (4) surveys of blue-collar employees, supervisors, and white-collar employees. The study focused on the following topics: (1) manufacturing in the 21st century; (2) discretionary effort and the organization of work; (3) market dynamics and work organization in the steel, apparel, and medical electronic instruments and imaging industries; (4) workplace transformation and its effects on plants and workers; (5) measurement of the components of a high-performance work system; (6) performance effects of high-performance work systems; (7) the relationship between high-performance work systems and worker outcomes; (8) the effect of high-performance practices on earnings; and (9) the relationship between work systems and productivity growth. The study produced hard evidence that high-performance workplace practices, including employee empowerment and shop-floor participation, are not only good for workers but are also a major source of competitive advantage for companies. (Thirty-eight tables/figures are included. The bibliography contains 202 references.) (MN)