In the news this week is the national effort to cut hospital readmissions by penalizing hospitals with high rates. Dartmouth atlas has published this map of 2009 data showing regional variation in 30-day readmission rates. Hospital readmissions are sentinel events that often signal gaps in the quality of care provided to Medicare patients. There are many different reasons for higher readmission rates across certain regions and hospitals, including differences in patient health status, the quality of inpatient care, discharge planning and care coordination prior to discharge, and the availability and effectiveness of ambulatory services in the community. This report also demonstrates the importance of the general tendency of health care systems to use the hospital as a site of care. The combination of these factors will differ across communities and systems as each faces its own challenges in keeping patients well and out of the hospital.