An ACO is a group of health care providers that agrees to be accountable for the quality and cost of health care delivered to a defined population. ACOs are expected be launched in January 2012, under Section 3022 of the Patient Protection And Affordable Care Act, which allows Medicare to promote "accountability for a patient population and... encourages investment in infrastructure and redesigned care processes for high quality and efficient service delivery." Different financial models of ACOs have been proposed, but proponents understand the ACO concept as having three basic attributes:
1. The capability to provide, and manage with patients, the continuum of care across different institutional settings, including ambulatory care, inpatient hospital care and possibly post acute care
2. The ability to link payments to improved care and cost reductions
3. The capacity to support comprehensive, valid and reliable performance measurement