Accountable Care Organizations, fuelled by the Affordable Care Act, have continued to grow – more than 20% of physicians are now part of ACOs, just three years into the model’s creation -- despite some mixed reactions from physicians on elements of the ACO regulations. What factors are hindering ACO popularity, despite the program’s strong potential? What are the challenges? The opportunities? The results? CureMD caught up with one of the biggest ACO advocates in the country, Dr. Farzad Mostashari.