ASTRO greatly appreciates Congress’ action in 2015 to stabilize reimbursement for freestanding radiation oncology centers by passing the Patient Access and Medicare Protection Act of 2015 (P.L. 114-115). This legislation, combined with more than 200 members of Congress writing to oppose proposed cuts by the Centers for Medicare and Medicaid Services (CMS), has provided much-needed payment stability. This will allow radiation oncology to transition away from the antiquated “fee-for-service” model and toward the promise of alternative payment models (APMs) authorized under the Medicare Access and CHIP Reauthorization Act of 2015 (MACRA). The underpinnings of a successful transition require flexibility and opportunities to participate. New payment arrangements must avoid overly-prescriptive rules that inhibit a radiation oncologist’s ability to deliver personalized care based on specific cancer profiles, patient lifestyle considerations or other factors that impact treatment decisions. CMS should also prioritize implementation of alternative payment models developed by specialty societies, such as ASTRO, which have the buy-in around model design and quality metrics from the specialty society members. ASTRO is developing alternative payment models designed to improve quality, reduce costs and drive better value for Medicare and patients.It is critical that Congress and CMS look to specialty societies to incorporate robust quality improvement programs into alternative payment models and the Merit-based Incentive Program (MIPS) under MACRA. ASTRO has implemented a state-of-the-art radiation oncology practice accreditation program, APEx®, Accreditation Program for Excellent, to support quality improvement in radiation therapy practices. In addition, ASTRO has launched RO-ILS: Radiation Oncology Incident Learning System®, a national patient safety reporting system to facilitate safe radiation treatments. Congress and CMS should leverage these breakthrough programs to ensure that radiation oncologists can fully participate in APMs and MIPS under MACRA.