How have past changes in state health regulations and policy affected primary care physicians’ behavior and attitudes? Using the CTS data, researchers at Yale University established four broad measures of physician practice: 1) professional autonomy; 2) primary care physicians’ sphere of responsibility; 3) level of community services provided in the form of charity care and acceptance of Medicaid patients; and 4) differences in autonomy/responsibility between providers who primarily treat Medicare and/or charity patients and those who treat the privately insured. Using these measures, the research team evaluated the impact of three types of state policy on physician behavior: 1) regulation of managed care; 2) attributes of the state’s Medicaid system; and 3) state policies related to the infrastructure or capacity of the health care system. In addition to the CTS Physician Survey, the study utilized the Area Resource File and publications on state legislation. The goal of this project was to explore how state policies directly and indirectly affect physicians’ perceptions and behaviors.