All introductory health policy textbooks tread common ground.
They describe the basic features of the Medicaid and Medicare programs and highlight the tradeoffs between cost, quality, and access. They compare and contrast the US and Canadian or British health care systems and explain recent developments in the medical marketplace, such as managed care and the rise of large physician groups. What differentiates one book from another is disciplinary focus, the degree to which they incorporate recent findings from the health policy literature, their ability to explain complex concepts like moral hazard, and the general level of sophistication with which they approach health policy issues.
Howard DH. Introduction to US Health Policy: The Organization, Financing, and Delivery of Health Care in America. JAMA. 2008;299(1):97-102. doi:10.1001/jama.2007.22