Enacted as part of the 2010 Patient Protection and Affordable Care Act, the Independent Payment Advisory Board (IPAB) was hailed by many analysts as a major innovation in US health policy making and cost control. The board promised to put a brake on Medicare spending through an extraordinary combination of budgetary discipline, expert advice, uncommon legislative procedures, and administrative delegation. IPAB embodied the aspirations of technocracy: the board would rise above partisanship and interest group pressures, formulating Medicare policy recommendations based on evidence and reason rather than politics. The special legislative rules and administrative powers associated with IPAB were to be an antidote to both congressional inaction and micromanagement. Those aspirations resonated with many politicians, policy makers, and health services researchers. Yet IPAB has fallen far short of the aspirations and enthusiasm that accompanied its establishment. It has remained in political purgatory, paralyzed by controversy and partisanship. We explore why IPAB has failed to live up to the hype and what the IPAB story tells us about the promise and limits of technocracy in US health care policy.