This article examines the recent pattern and progress of health care reform in affluent democracies, focusing in particular on Britain, Canada, Germany, the Netherlands and the United States. Its main contention is that efforts to reform health care in advanced industrial states have been marked by a paradoxical pattern of ‘reform without change and change without reform’, in which large-scale structural reforms have had surprisingly modest effects yet major ground-level shifts have, nonetheless, frequently occurred as a result of decentralized adjustments to cost control. The main task of the article is to investigate the reasons for and effects of this puzzling pattern by plumbing the largely unexplored theoretical territory between comparative health policy analysis and cross-national research on the welfare state. Along the way, the article develops a simple model of the politics of reform that helps explain cross-national variation in legislative and policy outcomes – particularly outcomes that occur through decentralized processes of internal policy ‘conversion’ and policy ‘drift’, rather than through formal legislative reform. It also takes up a number of other intriguing issues raised by recent trends: why, for example, market reforms are clustered in centralized political and medical frameworks; why these reforms have generally enhanced state authority rather than market autonomy; why, despite fragmentation, decentralized political and medical systems shifted towards an expanded government role; and why significant retrenchment of the public-private structure of health benefits occurred in the United States.