The Impact of Accountable Care: Origins and Future of Accountable Care Organizations

Accountable Care Organizations (ACOs) represent a changing dynamic in the American health care system. Instead of being paid for each service (tests, procedures, etc.) providers will increasingly be paid to manage the health of populations.

The Issue

Improving the patient care experience and the health of populations while reducing per capita costs of care are major driving forces for health system delivery and payment reforms. This issue brief provides an overview of the accountable care movement; describes the structural classification of ACOs and various accountable care payment contracts; and provides a high-level trend analysis of where the ACO movement is headed.

Key Findings

  • ACOs adopt financial accountability for the health care needs of a population.

  • ACOs coordinate care among providers and manage care of its population across the health care continuum.

  • Despite similar objectives, there is considerable variation across the market regarding ACO organizational structure, ownership, and patience care focus.

  • Medicare, state Medicaid plans, and commercial health insurers have adopted accountable care models.


In less than five years, accountable care has transformed from an academic idea to a tangible model: ACOs now exist in all 50 states and provide care for more than 23 million people. Both commercial and public ACOs have seen success at reducing cost and improving quality.   

About the Grantee

This issue brief, one of six in a series called “The Impact of Accountable Care,” was prepared by the National Business Group on Health and Leavitt Partners with RWJF support. In 2015, National Business Group on Health surveyed large employers (average 55,000 U.S. employees each) for their reactions to ACOs.