Atrius Health formed in 2004, is a not-for-profit, 501(c)(3) tax-exempt organization, and is the largest independent multi-specialty medical group in the Northeast. Atrius Health medical groups provide primary and specialty care from 30 locations in Eastern Massachusetts. Each year, Atrius Health’s 750 physicians and their medical teams coordinate patient care for 675,000 patients in over 2.2 million visits annually.
The Atrius Health groups have a long history of operating as a model for Accountable Care Organizations (ACO), with full responsibility for the quality and cost of care for many of their patients since before the term was coined by Elliott Fisher, MD, MPH, in 2006. In 2009, Atrius Health became one of the first organizations to sign on to the Blue Cross Blue Shield of Massachusetts Alternative Quality Contract (AQC), viewed by many as one of the first models of an Accountable Care Organization. Atrius Health is also a participant in the Centers for Medicare & Medicaid Service’s Pioneer ACO program. In 2014, Atrius Health’s Pioneer ACO was the highest quality Pioneer ACO in New England and the second highest in the country.
The Atrius Health primary care practices have received the highest possible national accreditation as Level 3 Patient-Centered Medical Homes from the National Committee for Quality Assurance (NCQA).
Atrius Health has also earned Stage 7 recognition from HIMSS Analytics, the highest level possible nationally for the use of health information technology. 
Patients of Atrius Health can access a secure patient portal to allow access to medical records and communicate securely with doctors online.
Atrius Health Medical Practices
Beth Israel Deaconess Medical Center
Beth Israel Deaconess Hospital – Milton
Beth Israel Deaconess Hospital – Needham
Brigham and Women's Hospital
Boston Children's Hospital
Lahey Hospital & Medical Center
Lowell General Hospital
Massachusetts Eye and Ear Infirmary
Metrowest Medical Center
Mount Auburn Hospital
New England Baptist Hospital
South Shore Hospital
- 2004: Dedham Medical Associates, Harvard Vanguard Medical Associates, Southboro Medical Group and South Shore Medical Center formed HealthOne Care System.
- 2005: Granite Medical Group joined HealthOne Care System.
- 2007: HealthOne Care System changed its name to Atrius Health.
- 2007: Hired Dr. Ed Noffsinger, the “Father of Shared Medical Appointments” to launch a program of Shared Medical Appointments (SMAs) as a way for patients to have better access to their physicians and other providers and to learn from other patients during a 90-minute group visit.
- 2009: Began working with Simpler Consulting to improve care deliveries through Lean transformation.
- 2009: Signed a five year Alternative Quality Contract (AQC) with Blue Cross Blue Shield of Massachusetts to improve the quality of care and cut medical costs.
- 2009: Created the Atrius Health Foundation to support innovative solutions to improve healthcare and help in emergency situations like the 2010 earthquake near Port-au-Prince, Haiti.
- 2011: Reliant Medical Group (formerly Fallon Clinic) joined Atrius Health.
- 2013: VNA Care Network & Hospice joined Atrius Health; VNA of Boston merged into VNA Care Network & Hospice
- 2015: Harvard Vanguard Medical Associates, Dedham Medical Associates, and Granite Medical Group merge into one corporation with VNA Care Network Foundation as an integrated subsidiary.
There is a notable disparity between Atrius' self reported vote of confidence and actual opinions on their healthcare strategies specifically in regards to leadership, furthermore some might disagree with current policies on medical marijuana vocal opponent Dr. James Broadhurst leader of a subsidiary group has spearheaded the policy, often citing anecdotal data. yet endorsing isolated forms of the constituent chemicals despite their proven inferiority as a mode of ingestion for many of their prescribed uses.
- "Atrius Health - About Us".
- "ACO FAQs".
- Johnson, Avery (March 28, 2011). "The Model of the Future?". Wall Street Journal.
- Aiello, Marianne (December 2, 2010). "Elliott Fisher: Data-Driven ACO Visionary". Health Leaders Media.
- "Edward B. Noffsinger".
- Donnelly, Ally (December 1, 2008). "Shared Medical Appointments Help Provide Better Care". NECN.
- TERGESEN, ANNE (December 19, 2009). "Group Healing". Wall Street Journal.
- ROSE, JILL (August 1, 2011). "On the Road". Inside Healthcare.
- "Lean Transformation".
- N/A. "Fee for Service: How Long Will It Be Around?: New Payment Models: Do They Help?". Medscape.
- Syre, Steve (September 16, 2011). "Hospitals’ cost gamble". Boston Globe.
- Butler, Brandon (June 21, 2011). "Fallon Clinic To Join Atrius". Worcester Business Journal.