Project Summary/Abstract This application is being submitted in response to the Notice of Special Interest (NOSI) identified as NOT-CA-23-044. The Stanford Cancer Institute’s (SCI) [2P30CA124435-14] mission is to leverage the broad and unique strengths of Stanford University in basic science, bioengineering, population science, biostatistics, technology development, clinical research, clinical care, and translation to (1) improve the diagnosis, treatment, and outcomes of cancer patients; (2) understand cancer etiologies among diverse populations; and (3) decrease cancer incidence in the SCI catchment area and beyond. SCI is committed to understanding and addressing the cancer burden and reducing cancer disparities in our community. This proposal is in direct response to a request from the SCI Community Advisory Board to foster research on strategies to reduce disparities in access to evidence-based cancer care services in the catchment area at the patient and community level. Cancer research discoveries over the last 30 years have stimulation critical innovations in cancer prevention and care delivery, greatly improving cancer survival. However, communities with the greatest cancer burden are often last to benefit from these innovations. Community benefit policies, including medical financial assistance and community-building initiatives, aim to incentivize hospital systems to address the needs of underserved patients and communities. Yet, the effectiveness of these policies in addressing persistent disparities in cancer care access and burden are largely unknown. Building on our prior research on community benefits, this proposal aims to engage community and health system partners in the development of more equity-focused community benefit policies to improve cancer outcomes and reduce disparities. Specifically, we seek to understand the complex and interacting factors that drive community benefit spending in order to inform equity-focused allocation decisions in the 10-county SCI catchment area. Activities proposed in this research supplement will establish a foundation for future research studies to develop and validate a simulation-based tool to inform the allocation of community benefits in ways that better address critical financial assistance needs for cancer patients and foster a more equitable allocation of community benefit resources.