In this chapter, I review the development of research on performance measurement and management (PMM) in the public sector informed by institutional theory. In doing so, I pay particular attention to how organisations deal with the ambiguity that is often inherent in PMM practices in the public sector and how this affects the process of institutionalisation. Prior research exploring this topic has tended to portray the process of institutionalisation as a relatively orderly or disorderly phenomenon. By contrast, I offer some suggestions as to how future research may evolve into a unified, conceptual perspective with a reasonably balanced emphasis on how ambiguous PMM practices are implicated in creating both institutional order and disorder. I argue that such a perspective may be nurtured by paying closer attention to the framing strategies that are implicated in the process of institutionalisation across multiple levels of analysis.