The growing focus on health care quality has led to the development of several Web sites that make hospital quality information publicly available to consumers. This study evaluated six such Web sites (the Centers for Medicaid and Medicare Services' Hospital Compare, the Joint Commission's Quality Check, the Leapfrog Group, and three commercial sites) for ease of use, data accuracy, and consistency of hospital rankings for several surgical quality measures. In general, the governmental and non-profit Web sites were rated as easier to use and had more complete information. However, the authors found significant variation in the risk adjustment methods used and the types of outcomes reported on each Web site, leading to poor reproducibility of rankings for specific surgical procedures.