Veterans Health Information Systems & Technology Architecture (VistA) - This is a comprehensive electronic health record (EMR) and practice management system system originally developed by the U.S. Department of Veterans Affairs (VA). The software is in the public domain and is installed in several thousand public and private hospitals and clinics around the world and supported by a number of public organizations and health IT corporations.

VistA is built on a client-server architecture, which ties together workstations and personal computers with graphical user interfaces at Veterans Health Administration (VHA) facilities, as well as software developed by local medical facility staff. VistA also includes the links that allow commercial off-the-shelf software and products to be used with existing and future technologies.

For more information about VistA, download a copy of the VistA Monograph.

* Also, check out OSEHRA, MedSphere Open VistA, vxVistA, and RPMS.