This report is intended to help Congress address the complex issue of hospital readmissions. It is largely conceptual and does not track legislation moving through the House and Senate.4 After helping to define the issues, this report discusses some of the diverse causes of hospital readmissions. It also provides a summary of approaches used to distinguish which hospital readmissions might be preventable. Finally, to help Congress evaluate strategies to reduce readmissions, this report includes a discussion of various strategies to lower the incidence of Medicare-covered hospital readmissions.