U.S. physicians and hospitals are experiencing serious difficulties obtaining affordable professional liability insurance. The current system, furthermore, often fails to provide compensation to injured people and does little to promote patient safety. To inform the development of an alternative approach, this project will examine the design and experience of the no-fault administrative systems used to compensate medical injuries in Sweden, New Zealand, Denmark, and Finland. The study will address the criteria used to determine which medical errors are compensable; the process used to develop the criteria; and the performance of these criteria in terms of efficiency, reliability, validity, and fairness to patients and providers. Findings will help stimulate interest in a potentially more promising option for malpractice reform. A paper discussing the study's findings will be submitted for consideration as a Health Affairs Web Exclusive. http://www.harvard.edu