Six million Americans have heart failure (HF), a debilitating, progressively chronic disease that is difficult to manage and profoundly impacts quality of life and survival. Racial and ethnic minorities (e.g., Black and Hispanic patients) tend to have more HF-related risk factors (e.g., diabetes, hypertension) and disproportionately higher HF prevalence. These populations are affected by significant disparities in HF care and outcomes as they are more likely to have their incident HF diagnosed in acute care settings, less likely to see an HF specialist or receive guideline-directed medical therapy (GDMT), more likely to have poor health- related quality of life, and more likely to have worse HF outcomes (e.g., mortality). Meanwhile, women have underutilized appropriate non-pharmacologic therapies across the spectrum of HF severity, with Black women most impacted by biases in the allocation of evidence-based HF therapies. Structural racism and discrimination (SRD) are pervasive throughout the current system of HF care delivery in the U.S. and are key drivers of differential HF care and outcomes that systematically disadvantages patients. This proposal focuses on disadvantages related to patient race, ethnicity, sex, socioeconomic status, and other identities. Our preliminary data suggest that the social structure of care delivery—the pattern of social relationships, practices, and institutions determining the nature and context of care delivery—is a major contributor to SRD in HF care. Our proposal focuses on examining HF care delivery networks within this structure (i.e., the social relationships of providers supporting HF care delivery within and across organizations). While evidence-based HF care and outcomes require robust care delivery networks, networks serving racial and ethnic minority populations and others disproportionately affected by SRD in HF care delivery are systematically weaker, contributing to poorer access, care coordination, and outcomes. Large-scale evaluations of the determinants of these systematic differences are lacking. As care delivery networks are shaped by health system and payer priorities and strategic plans, their evaluation would identify intervention points to reduce HF care and outcome disparities. Moreover, the rigor and impact of interventions are enhanced by incorporating stakeholder perspectives (health system and payers, patients, community) into the design of best practices. Our long-term goal is to advance equitable care and outcomes for populations disproportionately affected by SRD in healthcare delivery. This mixed methods proposal will address SRD in HF care by examining determinants of disparities and identifying stakeholder-informed areas of intervention within care delivery networks to inform a toolkit to enhance equitable HF care and outcomes. There are three aims: (1) Evaluate the “social structure of care delivery” for populations disproportionately affected by SRD in HF care delivery and outcom...