IN THIS ESSAY, we offer a new synthesis of American business history that aims to replace, but also subsume, the dominant Chandlerian framework. Writing in the mid-1970s, Alfred D. Chandler, Jr., attributed the success of the U.S. economy in the twentieth century to the rise of large, vertically integrated, managerially directed enterprises in the nation's most important industries. These enterprises, Chandler argued, were dramatically more efficient than the small, family-owned and managed firms that previously had characterized the economy. Where small firms were dependent on the market to coordinate their purchases of raw materials and the sale of their output, large firms took on these supply and marketing functions themselves, using hierarchies of salaried managers to coordinate them administratively. This visible hand of management, Chandler claimed, represented such a vast improvement over the invisible hand of the market that firms that developed these capabilities were able not only to dominate their own industries but to diversify into other sectors of the economy and attain positions of power there as well.