This article examines the cases of three health care states — two of which (Britain and the Netherlands) have undergone major policy reform and one of which (Canada) has experienced only marginal adjustments. The British and Dutch reforms have variously altered the balance of power, the mix of instruments of control, and the organizing principles. As a result, mature systems representing the ideal-typical health care state categories of national health systems and social insurance (Britain and the Netherlands, respectively) were transformed into distinctive national hybrids. These processes have involved a politics of redesign that differs from the politics of earlier phases of establishment and retrenchment. In particular, the redesign phase is marked by the activity of institutional entrepreneurs who exploit specific opportunities afforded by public programs to combine public and private resources in innovative organizational arrangements. Canada stands as a counterpoint: no window of opportunity for major change occurred, and the bilateral monopoly created by its prototypical single-payer model provided few footholds for entrepreneurial activity. The increased significance of institutional entrepreneurs gives greater urgency to one of the central projects of health policy: the design of accountability frameworks to allow for an assessment of performance against objectives.