IMPORTANCE: Community health worker (CHW) programs may improve health outcomes, increase quality of life, and reduce hospitalizations and cost of care. However, knowledge is limited on the barriers and facilitators associated with scaling evidence-based CHW programs to maximize their public health outcomes. OBJECTIVE: To identify barriers and facilitators to implementing an evidence-based CHW model. DESIGN, SETTING, AND PARTICIPANTS: This qualitative study examined perspectives of Individualized Management of Person-Centered Targets (IMPaCT) program staff (health system leaders, program managers, and community health workers) and patients receiving the intervention between March 9, 2020, and July 22, 2021, at 5 institutionally and geographically diverse health systems across the US. The collected data were analyzed between December 1, 2021, and April 27, 2022. Program staff were recruited via purposive sampling, and patients were recruited via convenience sampling. INTERVENTION: The disease-agnostic IMPaCT CHW model includes a standardized implementation approach and a structured set of theory-informed intervention components to create and achieve individualized action plans. MAIN OUTCOMES AND MEASURES: Interview guides were informed by the Consolidated Framework for Implementation Research. A rapid qualitative analytic technique was used to identify key themes, which were categorized into barriers and facilitators associated with framework ecological domains. RESULTS: Of a total 41 individuals invited, 39 agreed to participate (95% response rate; mean [SD] age, 45.0 [12.6] years; 30 women). General barriers included economic and policy constraints, including insufficient funding for CHW programs, clinical integration challenges, and CHW difficulty with maintaining boundaries. Program-specific barriers included insufficiently tailored materials for certain populations and upfront and ongoing program costs. General facilitators included CHWs' interpersonal skills and life experiences. Program-specific facilitators included the model's strong evidence base, supportive implementation team, and program design that enabled relationship building and engagement. Additional themes were cited as both barriers and facilitators, including the COVID-19 pandemic, organizational leadership, IMPaCT training, and program fidelity. CONCLUSIONS AND RELEVANCE: These findings suggest growing recognition of the importance of CHWs to improving health equity and population health. Barriers identified point to important policy and practice implications for CHW programs more broadly, including the need for continued attention to improving clinical integration and the need for sustainable program financing to preserve the longevity of this workforce.