Has the accountable care organization experiment been successful?—Yes.
Accountable care organizations (ACOs) have emerged as a prominent alternative to traditional fee-for-service payment. What was initially conceptualized as a pilot program for physicians to take responsibility for improving quality and slowing spending has become a national movement now covering more than 28 million Americans, 60% of whom are under commercial ACO contracts.1 Limited evidence on the effectiveness of the ACO model to date, however, has led some to question the merits of this approach to delivery system reform. However, it would be a mistake to reverse course so early in the life of this promising payment and delivery model.