The field of health policy and systems research (HPSR) has demonstrated an interesting maturation over the past 20 years. The number of publications and the numbers of researchers engaged in HPSR have all grown substantially during recent years. In this chapter we seek to explain why and how this growth has occurred. Clearly one of the key factors driving interest in HPSR is the growing global attention to health systems strengthening. As for many new fields of endeavour or study in the area of development, the evolution of HPSR reflects a constant back and forth between individual country interests and aspirations, on the one hand, and global-level processes, on the opposite. Given the diversity of country incidents and responses, global-level operations are often more visible and noticeable. However, this focus means that we inevitably provide a partial view of the forces that have shaped HPSR in individual countries. A final critical challenge in the HPSR field during the mid-1990s was a lack of demand for evidence to inform decision-making about health-systems strengthening. The field of data translation was still nascent; indeed, it had been not until the late 1990s and early 2000s that the term “knowledge translation” became widely wont to report the process of reinforcing the execution of key research findings. One of the most significant factors driving increasing interest in the field has been the recognition of the importance of strong health systems.