NAACOS: A Brief History

In October 2012, a small group of ACO senior executives gathered at a Nashville airport hotel to brainstorm about how best to structure and launch ACOs in response to federal opportunities in Medicare. At the time, ACOs were forming rapidly and interacting with the Centers for Medicare & Medicaid Services (CMS), yet ACOs lacked a cohesive voice or even an effective way to exchange ideas. To fill this void, NAACOS was launched to ensure ongoing and sustainable advocacy and education for the ACO industry. Led by founding Board Member Stephen Nuckolls and a small band of ACO leaders and experts, NAACOS took shape in just a few months, becoming an effective voice for the ACO community. Throughout its history, NAACOS has remained true to its roots as a group formed by ACOs, governed by ACOs, and wholly focused on ACOs.

Over the past decade, the ACO model has evolved from an academic concept to a market-based solution to fragmented and costly care that enables local physicians, hospitals, and other providers to work together and be responsible for improving quality, enhancing patient experience, and reducing waste to keep care affordable.  

The history of NAACOS mirrors the rapid growth of ACOs. At the time of NAACOS’ founding, the organization had about 50 members. Today, NAACOS’ members include nearly half of the 700 ACOs that serve an estimated 23 million Americans covered by Medicare, commercial insurance, and Medicaid across local communities in all 50 states.

Initially, NAACOS focused on ensuring effective ACO participation in public policy deliberations. With an interim board and just a few staff members, NAACOS CEO Clif Gaus focused on gaining a “seat at the table” in key federal ACO policy discussions.  “In Clif, we were fortunate to find a CEO with decades of experience working on the forefront of federal health care policy,” said Nuckolls, CEO of Coastal Carolina Health Care, PA, and its ACO, Coastal Carolina Quality Care, Inc.

“ACOs needed an experienced and credible voice in the policy process, and Clif immediately provided that,” said Mike Barrett, Co-founder Cura Management, Inc. Working with the board and the NAACOS ACO member community, Gaus provided sound, consistent, and workable solutions to CMS early in the agency’s ACO policy deliberations. Today, NAACOS members continue to have unprecedented access to leadership at CMS and the Center for Medicare and Medicaid Innovation, for example via “open mic” sessions at NAACOS conferences.


Beyond advocating for workable policy,NAACOS’s mission grew to include training and educational offerings that are vital to the ACO community. Then and now, NAACOS focuses on providing programs that are relevant to real-world, day-to-day ACO operations. “At the outset, NAACOS needed to be concrete in its educational offerings to stay viable, and so in those early workshops, the focus was quite pragmatic.”

In 2017, recognizing the scarcity of objective science on accountable care strategies, NAACOS provided seed funding to launch the Institute for Accountable Care, a 501(c) (3) nonprofit organization with a mission, first, to build the evidence base on the impact of ACOs on both quality and cost, and second, to identify and disseminate best practices used by ACOs to improve population health.

While the Institute will benefit from unique access to NAACOS’ membership, the Institute is a separate organization and conducts independent and objective research. The two organizations cooperate on select projects, working with NAACOS members to implement results of research and demonstration projects.

Key NAACOS Milestones

  • October 2012: NAACOS launches with 50 ACO members.
  • January 2013: CEO and interim NAACOS Board selected.
  • March 2013: First Policy & Operations Conference in Baltimore with 150 attendees, featuring open mic opportunity with CMS.
  • June 2013: Inaugural NAACOS Board elected.
  • September 2013: NAACOS opposes CMS Proposed Changes to ACO Quality Benchmarks
  • January 2014: NAACOS releases results from First Ever Survey of ACO First Year Start-Up Costs and IT Spending 
  • February 2014: The NAACOS MSSP Data Task Force submits to CMS an analysis of the shortcomings in the current data feeds and reports and makes a number of recommendations for improvement.
  • March 2016: NAACOS and other prominent organizations submit comments to CMS on Regional Benchmarking proposed rule. NAACOS submits comments on Health Care Payment Learning & Action Network (LAN) Financial Benchmarking White Paper.
  • June 2016: NAACOS publishes ACOs at a Crossroads White Paper.  
  • December 2016: NAACOS and others submit comments to CMS on developing Track 1+ ACOs.
  • June 2017: NAACOS provides seeding funding for the Institute for Accountable Care.
  • August 2017: NAACOS submits comments to CMS on 2018 Quality Payment Program proposals.
  • January 2018: CMS announces 561 Medicare Shared Savings Program (MSSP) ACOs for 2018.
  • February 2018: NAACOS and five other provider organizations send a letter to CMS requesting that MSSP ACOs meeting cost and quality criteria be able to remain in Track 1.
  • September 2018: Study shows ACOs saved Medicare $1.84 Billion from 2013 to 2015. Nine stakeholder groups urge CMS to ensure continued success of ACO program.
  • October 2018: NAACOS submits comments on CMS Pathways to Success proposed rule. 

NAACOS is the voice of ACOs to CMS, the White House and on Capitol Hill. Members also benefit from NAACOS operational resources for starting and maintaining successful ACOs. Join today!