The Veterans Health Administration’s open-source electronic health record system VistA is a fully integrated, enterprise-wide healthcare information system that has been developed and used for the past 20 years by the Veterans Health Administration, the largest, centrally directed, healthcare system in the U.S. VistA has been deployed in about 1,500 care sites. More private-sector oriented, open-source versions such as WorldVistA and OpenVista, whose source code is freely availabe could be an effective and low-cost option for non-Veterans Affairs hospitals that are seeking to implement a complete hospital information system, but have been held back by the cost.