Linda Aiken, PhD MSN, is director of the Center for Health Outcomes and Policy Research and The Claire M. Fagin Leadership Professor of Nursing and Professor of Sociology at the University of Pennsylvania in Philadelphia. Dr. Aiken's other appointments at the University of Pennsylvania include senior fellow at the Leonard Davis Institute for Health Economics and research associate in the Population Studies Center. Before joining the University of Pennsylvania faculty in 1988, Dr. Aiken served as vice president of the Robert Wood Johnson Foundation. She is a member of the Institute of Medicine, a fellow of the American Academy of Arts and Sciences and of the National Academy of Social Insurance, a former president of the American Academy of Nursing, a distinguished fellow of the Academy for Health Services Research and Health Policy (now AcademyHealth), and a member of the Council on the Economic Impact of Health System Change. Dr. Aiken served on the Medicare Physician Payment Review Commission for 6 years and was a member of the 1982 Social Security Advisory Council and of President Clinton's National Health Reform Task Force. Her recent work, for which she received the Sigma Theta Tau International Clinical Research Award in 1999, has focused on accounting for variation in hospital patient outcomes in the United States, Canada, the United Kingdom, and Germany. Dr. Aiken received her bachelor's and master's degrees in nursing from the University of Florida, Gainesville, and her doctorate in sociology and demography from the University of Texas at Austin.