Abstract : This paper provides a new mechanism to explain variation in firm productivity across locations: variation in the internal organization of labor into hierarchical layers, which are associated with different responsibilities within the firm. To guide my analysis, I develop a theoretical model that yields two implications. First, firms in larger markets organize into a greater number of layers. Second, because they have more layers, firms in larger markets are more productive. I then use administrative data to examine the model’s implications across French employment areas and non-tradeable service industries that satisfy the model’s assumptions: Clothing and Shoe Retail, Traditional Restaurants, and Hair and Beauty Salons. The findings are consistent with the model. I also observe that 8.8% to 22.4% of the log productivity gains from denser areas arise from differences in the organization of firms. A separate analysis shows that results are similar across firms operating in the manufacturing sector.