Dates of Program: December 2011 through May 2016.

Description: In December 2011, the Robert Wood Johnson Foundation launched a national program, Accountable Care Organizations: Testing Their Impact, to learn more about how accountable care organizations (ACOs) are evolving and how they influence the delivery of health care. The number of ACOs has increased from about 100 when the program started to 626 as of May 2014.

In a first round of funding (March 2013–March 2015), RWJF selected four research teams to produce qualitative case studies on ACOs serving the private health insurance market or Medicaid. Researchers are conducting two rounds of site visits, key informant interviews, and, in some cases, focus groups with patients and families. In a second funding round, RWJF will commission papers on predefined topics from subject matter experts.