This PhD thesis studies performance management (PM) in complex organizational settings. In both academia and practice, PM as a subject has received increased attention over the past couple of decades. In academia, it has been studied across several research paradigms and disciplines, through empirical cases, structured experiments and philosophical investigations. In practice, the subject is typically “owned” by Human Resource (HR) departments of large-scale international organizations. Typically, employees in all hierarchical positions of such organizations become acquainted with a PM system via the responsibility given to them at the beginning of the year for achieving a set of goals by yearend. A recurrent idea is that there should be a clear link between the organization’s overall strategies and the sub-goals of each division, department, line managers and employees. However, this thesis studies closely how PM practices do not merely produce tangible outcomes and clear links between predefined goals and outcomes. Instead, it shows how PM systems and practices are constituted through endless interactions and relations between devices, texts, humans and events. Based on this way of studying the world, this thesis illustrates how PM practices play different roles in shaping the organizing of work in sometimes surprising ways.