Health maintenance organizations, though in existence since about 1940, gained nationwide attention in the early 1970s as an efficient system for delivering health care services. Though initially condemned fry organized medicine as unethical, the HMO has today become a rapidly growing health care system, and one, according to the author, vital to the future of the private practice of medicine. The author sketches the history of third-party payers, and the role of the government in health care since the Depression and discusses its effect on private practice. The HMO, fostered by government action under the Nixon administration, is viewed as a pro-competitive wedge that will break the long-standing monopoly held by Blue Cross-Blue Shield, hospitals, and local medical societies. It is through the HMO or an HMO-like model that the future health care system will become more cost-effective, egalitarian, and accessible to those in need of services, the author says.