Objectives : This study was conducted to investigate the current status of outsourcing in Korean hospital information systems and the factors influencing its introduction. Methods : The authors surveyed 136 hospitals located in Seoul and its surrounding vicinities from June 7 to June 23, 2006. The facilitators and inhibitors to outsourcing in hospital information systems were derived from literature and expert reviews. Multiple logistic regression analysis was applied to identify the major influencing factors on outsourcing in hospital information systems. Results : Eighty-six (63.2%) of the 136 hospitals surveyed, which were mainly tertiary hospitals, responded to using outsourcing for their hospital information systems. "Hardware and software maintenance and support," "application development," and "management of service and staff" were the major areas of outsourcing. Outsourcing had been employed for $4sim7$ years by 45.5% of the hospitals and the proportion of the budget used for outsourcing was less than 20%. A need for an extension in outsourcing was agreed on by 76.5% of the hospitals. The multiple logistic regression analysis showed that both consumer satisfaction and security risk have an influence on hospital information system outsourcing. Conclusions : Outsourcing in hospital information systems is expected to increase just as in other industries. One primary facilitator to outsourcing in other industries is consumer satisfaction. We found that this was also a facilitator to outsourcing in hospital information systems. Security risk, which is usually considered an inhibitor to information technology outsourcing, was proven to be an inhibitor here as well. The results of this study may help hospital information systems establish a strategy and management plan for outsourcing.