Public organizations have traditionally been geared to reducing uncertainty by means of standardization and hierarchical control. In recent decades, managerial reforms and digitalization have made it possible to put public officials’ work under even closer scrutiny and control. At the same time, however, frontline discretion is seen as essential in today’s horizontal forms of service provision and law enforcement. Notions such as trust and collaboration are not predefined, but left open for frontline officials’ professional expertise. This doctoral dissertation examines how frontline officials who work in a bureaucratic context and have been granted considerable discretion, experience uncertainties and attempt to reduce these uncertainti...