The expansion of markets and industrialization greatly increased the benefits of specialization in the U.S. economy. However, since the benefits of specialization can only be realized through trade, specialization significantly increases the volume of market transactions in the economy. The analysis presented in this paper suggests that a better understanding of the historical changes in the nature of market transactions costs, especially those related to information, is likely to provide considerable insights on the rise of the modern business enterprise and a richer understanding of the industrial organization of the U.S. economy.