Cancer care is transforming, moving toward increasingly personalized treatment with the potential to save and improve many more lives. Many oncologists and policymakers view current fee-for-service payments as an obstacle to providing more efficient, high-quality cancer care. However, payment reforms create new uncertainties for oncologists and may be challenging to implement. In this article, we illustrate how accountable care payment reforms that directly align payments with quality and cost measures are being implemented and the opportunities and challenges they present. These payment models provide more flexibility to oncologists and other providers to give patients the personalized care they need, along with more accountability for demonstrating quality improvements and overall cost or cost growth reductions. Such payment reforms increase the importance of person-level quality and cost measures as well as data analysis to improve measured performance. We describe key features of quality and cost measures needed to support accountable care payment reforms in oncology. Finally, we propose policy recommendations to move incrementally but fundamentally to payment systems that support higher-value care in oncology.