The paper examines four different cases in which performance measurement has been applied within a process of policy reform. The cases will demonstrate that a large variety of mechanisms may underlie the use of performance measurement instruments, ranging from institutional imitation to political pressures. They show that it is insufficient to study performance measurement problems merely from the classical principal-agent perspective, simply because governance systems frequently lack an institutionalised principal-agent relationship. One must travel down new avenues of research to understand this phenomenon more fully, a journey for which this paper provides some preliminary directions.