This article describes the theoretical foundations of government policy for hospitals in terms of correcting market failure and enhancing equity. It then discusses the characteristics that desirable payment systems should have, and the effects of the DRG-based prospective payment system on hospital behavior, its financial performance, hospital industry, and health care expenditure. The rationales and impacts of other public policies for hospitals such as antitrust and fair trade regulation, dissemination of practice guidelines and hospital mortality information, regulation of hospital capital investment, and tax policy are also discussed.