Are heterogeneous labor market outcomes a product of markets efficiently allocating resources or the result of structural market failures which should be corrected through well-crafted policy? In order to address this fundamental question in modern economics, we must first understand the forces which shape individuals' earnings, employment, and occupational choices. This collection of essays provides new evidence to support several novel channels which influence labor markets. First, I evaluate the connection between technological change and labor market outcomes by bringing new data and methods to study the mechanization of American agriculture in the early 20th century. Using an instrumental variables estimation strategy, I find that exogenous increases in exposure to technological change generated occupational displacement for incumbent laborers, increased income inequality, and had important impacts on intergenerational mobility for the children of affected workers. Additionally, I investigate the connection between low-opportunity neighborhoods and public housing residents' labor market outcomes. Leveraging quasi-random variation in neighborhood quality due to a public housing demolition, I find that residents' wages increased after moving to higher-opportunity neighborhoods and that more intense supportive services improved post-move employment. Taken together, these essays provide new evidence that both large-scale factors like new technologies and local factors like neighborhood quality contribute to heterogeneity in labor market outcomes both historically and up to the present day.