In this article, we will further the explanation of the state's changing role in health care systems belonging to the Organisation for Economic Cooperation and Development (OECD). We build on our analysis of twenty-three OECD countries, which reveals broad trends regarding governments' role in financing, service provision, and regulation. In particular, we identified increasing similarities between the three system types we delineate as National Health Service (NHS), social health insurance, and private health insurance systems. We argue that the specific health care system type is an essential contributor to these changes. We highlight that health care systems tend to feature specific, type-related deficiencies, which cannot be solved by routine mechanisms. As a consequence, non-system-specific elements and innovative policies are implemented, which leads to the emergence of "hybrid" systems and indicates a trend toward convergence, or increasing similarities. We elaborate this hypothesis in two steps. First, we describe system-specific deficits of each health care system type and provide an overview of major adaptive responses to these deficits. The adaptive responses can be considered as non-system-specific interventions that broaden the portfolio of regulatory policies. Second, we examine diagnosis-related groups (DRGs) as a common approach for financing hospitals efficiently, which are nevertheless shaped by type-specific deficiencies and reform requirements. In the United States' private insurance system, DRGs are mainly used as a means of hierarchical cost control, while their implementation in the English NHS system is to increase productivity of hospital services. In the German social health insurance system, DRGs support competition as a means to control self-regulated providers. Thus, DRGs contribute to the hybridization of health care systems because they tend to strengthen coordination mechanisms that were less developed in the existing health care systems.