Background: Modern cancer care faces increasing complexity and the challenge of delivering consistent, high-quality care across growing networks. Dana-Farber Pathways address these concerns by translating expert content into treatment algorithms delivered through a web-based platform and implemented across the network. We had previously built 31 Medical Oncology (MO) pathways. Our goal was to build and implement Radiation Oncology (RO) pathways for common cancer conditions in 18 months. Methods: Partnering with lead clinicians from each disease group, we chose the most appropriate framework for each pathway: expand previously established RO pathway; use corresponding MO pathway; or if no framework was available, develop RO pathway in its entirety. We worked with each disease group to gain consensus about the recommended on-pathway selections that reflect the latest research and institutional standard of care. Implementation consisted of pre- and post-launch department communications about metric goals and individual provider training on the system. Because the program was launched without provider incentivization, the usage rate goal was navigations for at least 25% of patients receiving radiation treatment. The on-pathway rate goal range was 70-80%. Results: We exceeded our goal: we built and implemented 25 pathways in 12 months and constructed all 27 pathways in 18 months. We have met both key rate goals across all disease pathways since time of launch: usage rate is 63%; on-pathway rate is 85% (39 providers across 3 sites). Conclusions: A preliminary analysis of RO Pathway data demonstrates collective adoption across all sites. Qualitative surveys show it to be a useful resource in radiation treatment decision-making and in palliative care service. We will continue to analyze the use of RO Pathways and develop strategies to collaborate with MO to further guide multi-disciplinary decision-making.