Using original survey data and secondary analyses of data from the American Hospital Association and the Centers for Medicare & Medicaid Services, this is an index of hospital quality updated on an annual basis. This index has three components designed to represent three key aspects of care-structure, process, and outcome. More than 900 hospitals are listed in Cancer. All are experienced in treating difficult cases—a hospital is listed only if at least 417 inpatients who needed a high level of expertise in this specialty were treated there, or if surveyed specialists recommended the hospital for such patients. The top 50 hospitals are ranked by score. Those below the top 50 are listed alphabetically.