Powering Healthcare for Over 35 Years.

VistA stands for “Veterans Information Systems and Technology Architecture.” Originally created in the late 1970s, VistA has benefited from more than 35 years of continuous, clinician-driven improvement. Today’s VistA serves nearly 9 million Veterans as part of the largest healthcare system in the United States. It is a comprehensive system for managing both large and small healthcare facilities, providing functions ranging from prescription refills to employee timekeeping.

In addition to its deployment by VA, VistA serves more than 1,800 hospitals and other healthcare providers around the world. In fact, a 2011 survey conducted by the American Academy of Family Physicians ranked VistA’s primary user interface in the top 10 for user satisfaction, and first in several other categories. The findings have been confirmed by a Medscape 2016 survery The newest major implementations are the “Empire State VistA” system, planned to cover mental health services at 23 hospitals and over 300 clinics throughout the State of New York; and the "EPI VistA System" at the Tennessee Department of Health (TDH), implemented over the entire Tennessee State public health delivery system.

The early history of VistA can be found at A more recent history written by Arthur Allen is available at Politico's website

The Resource and Patient Management System (RPMS) was an early adoption of VistA by Indian Health Service (IHS) for use in an outpatient setting. It is tempting to call it a fork, but it is not -- RPMS made a conscious decision to keep the exact same code infrastructure as VistA, while incorporating different clinical applications. When this happened, between 1983 and 1986, VA did not offer outpatient services, while that was the vast majority of what IHS provided. By necessity, then, RPMS couldn't use all of the same functionality as VistA -- it was not what IHS wanted. The irony of history is that RPMS did eventually take some code from VistA when IHS needed some inpatient functionality; and the VA adopted a lot of RPMS's code to provide outpatient functionality for VistA.

IHS had an existing system called Patient Care Information System (PCIS) that provided a template of how RPMS should look: orientation to episodic visits; population health; and the use of the Problem List and Health Summary as a cornerstone of the medical record. PCIS was sunsetted in the mid-90s.

More information on RPMS's history can be found on Sam Habiel's website here.

Where do I begin?

You don't need to be a programmer to get started using VistA. Download a demo version of Computerized Patient Record System (CPRS), the primary doctor's user interface, and try it out today. To learn how to use CPRS, check out the CPRS User Guide: GUI Version or for a more in depth training, see the free, online interactive CPRS training course available from VA eHealth University.

OSEHRA provides source code and a variety of supporting resources to get you up and running on an OSEHRA VistA instance. To learn more, visit Getting Started. Next, we encourage you to engage with the OSEHRA community. This community is your window into a world of innovation and collaboration. Developers may wish to learn more and contribute to development, while providers considering a production installation should engage with OSEHRA corporate members or participate in free working groups to explore how their needs may best be addressed. If you have questions, send them to

Choosing a Distribution.

One of the many advantages of open source code is that anyone can customize it to meet particular needs. The resulting versions of the code are known as “distributions.” The version that is released by the government using the Freedom of Information Act request process is known as FOIA VistA. It is the basis for all other distributions. For example, the Indian Health Service's RPMS, based on VistA and geared toward ambulatory care. More recently, many commercial vendors in the community have modified and extended VistA to address their customers’ needs, and offer the software as a fully-supported solution. The three major VistA distributions with users in the community are WorldVistA by WorldVistA; vxVistA by DSS; and OpenVistA by Medsphere.

Here's a table comparing the various aspects of the three major community distributions:

Community Distributions Comparison
  WorldVistA vxVistA OpenVistA
License Open Source, under AGPL3 Open Source, under Apache 2 Proprietary (in spite of the name)
Latest release Latest release based on FOIA code from 2011 Latest release based on FOIA code from 2015 Unknown
Customer base Used in the US but has a bigger market outside of the US by companies that take it and customize it. US Install Base with commercial support provided by DSS, Inc. US Install Base with commercial support provided by Medsphere, Inc.
Support available? Commerical support not available by WorldVistA. Various companies provide support as needed. Commercial support available Commercial support available

OSEHRA produces a distribution called OSEHRA VistA, which is VistA as released under the Freedom of Information Act, plus changes to make it usable by the outside community on an open source stack, and enhancements obtained from the open source community and from the open source VistA distributions. This distribution is intended to be used for demoing and innovation; but not for patient treatment.

To learn more about the distributions of VistA, and find out which one might be the best for you, visit Distributions of VistA.

Benefits of an Open Source EHR

An open source VistA EHR solution offers:

  • Lower life cycle cost
  • The reliability of a proven solution
  • Reduced risk of obsolescence
  • The ability to improve your system without waiting for the next proprietary product release
  • A dynamic, free platform for development
  • For developers and integrators, there a is growing market for installation, customization, and support services

For more information, see our multimedia Open Source VistA EHR microsite.