At the turn of the twentieth century, most cities in America featured a patronage-based system of governance, but over the next few decades, patronage was replaced by civil service. Civil service restructured the relationship between elected officials and government employees, with employees benefiting from a variety of new protections. Yet in studying this change, scholars have largely ignored the role local employees themselves might have played in the transformation. We argue that city employees stood to benefit from civil service, and in places where they had agency and clout, they were important drivers of its adoption. We collected a dataset for more than 1,000 municipal governments, determining whether and when they adopted civil service and whether their employees were organized in an occupational organization. Our analysis of these new data shows the influence of city employees was an important contributor to the spread of civil service in American local government.