Networks of friends and relatives were the dominant channels of information and assistance in late-nineteenth and early-twentieth century labor markets. The information and assistance they provided directed the vast majority of long-distance migration and played an important role in the local allocation of labor as well. Nonetheless, the number and importance of employment agencies and labor exchanges did grow during the late-nineteenth century. The expansion of labor market intermediaries and other complementary businesses serving job seekers provided an important complement and extension to kin- and friendship-based networks that helped to encourage and expand European immigration in the decades after the Civil War. Their services were advertised in Europe by agents for steamship lines carrying passengers and were publicized through newspapers and other media. For potential immigrants who lacked well-placed friends and family to assist them in finding a job in the United States, the knowledge that there were employment agencies and other businesses to assist them upon arrival must have served to lower the expected costs of movement. At the same time, the rising volume of migration encouraged employers' continued reliance on immigrant labor. The mutually reinforcing nature of these decisions by immigrants and employers was central to the perpetuation of the geographic patterns of labor recruitment that had emerged in the decades before the Civil War.

Understanding the operation of the labor market intermediaries that emerged over the nineteenth century sheds considerable light on the broader issue of how labor market institutions worked at that time.