The employment records of a large northeastern manufacturing plant were analyzed to test the opportunity for career advancement within a large-scale industrial establishment. The employment records analyzed covered the years 1921 through 1937 and more than 28,000 different employees (male and female). The company was selected as being representative of industrial plants in general for several reasons. Both crude (X-type, or probable happenings for individuals in a single plant) and lifetime (Y-type, or probable happenings for individuals employed in a series of plants) probabilities were calculated during analyses of the following: patterns of entering, ascending, and leaving the corporate structure; promotion level; the relationship between education and the promotion-demotion process; the relationship between intelligence and the promotion-demotion process; and family influence in the promotion process. Education proved more important for career advancement to higher-level managerial/executive positions than to lower-level managerial/supervisory positions. Individuals with higher intelligence had a progressive advantage in climbing the corporate ladder. Finally, many of the individuals who reached the highest levels of company management could not have done so without their family ties. (Eighty-eight tables are included. Appendixes constituting approximately 40% of the book include 85 tables containing detailed information on the estimating procedures and methods used to calculate the various crude and lifetime probabilities analyzed in the study.) (MN)