Proper coordination of patient care is a hallmark of a high performance health system. However, the ability of health care organizations to measure the quality of coordination activities—and, similarly, their impetus for improvement—has been hampered by a lack of consensus on metrics and data collection strategies, and by a lack of tools to implement these measures. In this project, researchers at Johns Hopkins University, the National Committee for Quality Assurance, and the Park Nicollet Institute will team up to: 1) develop a comprehensive framework for measuring ambulatory care coordination that includes new data available through electronic health records (EHRs); 2) develop technical specifications for a series of care coordination measures that are applicable to practices with varying levels of EHR support; and 3) test the usability of the measures with 10 to 20 practice settings featuring varying levels of EHR support.