Hospitals and clinics have taken advantage of information systems to streamline many clinical and administrative processes. However, the potential of health care information technology as a source of data for clinical and administrative decision support has not been fully explored. In response to pressure for timely information, many hospitals are developing clinical data warehouses. This paper attempts to identify problem areas in the process of developing a data warehouse to support data mining in surgery. Based on the experience from a data warehouse in surgery several solutions are discussed.