AMERICA'S HEALTH CARE costs are rising. Spending on health care surpassed $1 trillion in 1996, making health care the country's single largest expense. The huge cost increases that have contributed to this sum make it difficult to provide quality health care services to everyone who needs them. This situation has led to changes in how health care services are provided. The most common form of health care delivery today is managed care, a system of monitoring and managing health care services, providers, and costs. The intent of managed care is to deliver the broadest array of health care services to the greatest number of people in the most efficient ways.

Efforts to achieve this balance have had mixed results. Most experts believe that managed care plans have successfully controlled costs while providing quality care for large numbers of people. Managed care has also been...