This chapter illustrates the impact of changing social and economic structures on harvest work, how these changes affected the work environment and labor relations, and how the state became an active agent in mediating between the conflicting claims of those with an economic interest in the proceeds of the harvest. There a number of reasons why the harvest period constitutes a suitable research area to delve into the ecologies of pre-industrial labor markets and work regimes. Although some farmers successfully challenged local and regional authorities, most regulations remained in full force until the end of the Old Regime. During the harvest of 1791 public officials in northern France used this new labor legislation effectively to intervene in conflicts between farmers and their harvest workers. Migrant labor created tensions in rural communities, both with their employers and the settled population. These tensions resulted in a growing body of local and regional regulation of harvest work.