Since the early 1980s, research on industrial organization has identified a new form of flexibly specialized production in which large vertically integrated firms engaged in mass production are being superseded by agglomerations of spatially dense networks of small vertically disintegrated firms. Empirical support for this thesis comes primarily from case studies of single industries or isolated regions. Very little is know about how movement toward vertically disintegrated industrial structures affects spatial agglomeration and industrial competitiveness at the national or subregional level. This project will test certain hypotheses relating spatial agglomeration, industrial organization, firm size, and industrial competitiveness with unique data sets for industries at the national level, and it should provide systematic statistical tests of key points of contention in the debate over flexibility in industrial structures. The project will map spatial patterns of agglomeration and vertical integration for selected industries, and it will compare agglomeration and vertical integration across regions by means of statistical tests of regression and analysis of variance. This research will add new knowledge about the geography of industrial organization in the U.S., and it will test some critical hypotheses about how changes in industrial structure affect changes in competitiveness at regional and national scales. It should further contribute to the debate about the impact of industrial restructuring on the agglomeration of leading edge industries in this country. At a theoretical level, the project will help settle some important questions about the tendency toward flexibly specialized production systems and their spatial concentration.