Background: Rising rates of substance use, particularly the use of synthetic opioids, have led to increases in fatal overdoses and injection-associated infections. Harm reduction, including infection prevention via provision of educational interventions and sterile syringes and other supplies, is an approach to minimize risk of severe outcomes. Although harm reduction services (HRS) are highly evidence-based, implementation in most healthcare settings has been limited. The aim of this study was to identify facilitators and barriers to the implementation of HRS to inform strategies for increasing access and facilitating the adoption of a comprehensive bundle of harm reduction resources within the VHA. Methods:Qualitative interviews were conducted using a semi-structured interview guide. Interviews explored how harm reduction is currently understood and implemented by VHA providers and elicited input on perceived facilitators and barriers to implementation. Data were analyzed using a directed content analysis. After barriers and facilitators were identified, they were mapped to relevant implementation strategies using the Consolidated Framework for Implementation Research - Expert Recommendations for Implementing Change (CFIR – ERIC) tool. Results:15 interviews with VHA providers (physicians, social workers, pharmacists, and directors of addiction and mental health services) were conducted across 5 sites. Multiple barriers and few facilitators to the provision of HRS were identified. Existing HRS were thought to be fragmented and dependent on the knowledge, time, and comfort level of individual providers. Participants also highlighted stigma around substance use, limited support, and burdensome regulatory requirements. Existing infrastructure, social programming, and local champions were highlighted as facilitators. Given these factors, implementation strategies that may be bundled to promote adoption of HRS include engagement of champions, communications and educational strategies, existing policies, and creation of dashboards, tracking, and feedback systems. Conclusions: HRS are effective and evidence-based, yet their adoption into traditional healthcare settings has been limited. Mapping of barriers to evidence-based implementation strategies may help improve integration of HRS into VHA healthcare, however, challenges addressing stigma remain a substantial barrier. More research is needed to identify implementation strategies that are most effective for addressing barriers imposed by stigma.