Millions of people suffer from undiagnosed or untreated chronic conditions. The Harvard Center for Integrated Approaches to Undiagnosed Diseases, which combines the resources of Brigham and Women’s Hospital, Massachusetts General Hospital, and Boston Children’s Hospital, along with a coordinating center at Harvard Medical School, are mentioned. Harvard Medical School’s Center for Biomedical Informatics, under the leadership of center director Isaac Kohane, Lawrence J. Henderson Professor of Pediatrics at Boston Children’s Hospital, will coordinate the national network.