The health supply chain (SC) system in Rwanda experienced a number of workforce-related challenges, including insufficient skilled supply chain management (SCM) professionals with the necessary competencies. The Human Resources for Supply Chain Management (HR4SCM) Theory of Change (TOC) provides a methodology to assess human resources (HR) management systems by explaining the preconditions required to achieve optimized workforce performance. We applied this model to design interventions to strengthen the Rwanda health SC workforce. We compared conditions in the health SC HR system in Rwanda with the 60 outcomes described as necessary for optimized workforce performance in the HR4SCM TOC model. We used a survey and participatory workshop at the central level, followed by structured interviews (N=35) with SC professionals in health centers, hospitals, and regional warehouses (N=20) in Southern Province and Kigali City to identify which outcomes already existed in the Rwandan HR system and which outcomes required strengthening through targeted interventions. We used focus groups (N=2) to refine interventions. We identified that 31 of the 60 outcomes were not sufficiently in place in the Rwandan health SC HR system. SCM workers had gaps in the technical and managerial competencies and did not have access to adequate training and professional development opportunities for certain required competencies. An SCM career path did not exist, and education was not available for all required SCM qualifications. Fourteen of these outcomes were prioritized for strengthening. We designed 20 workforce interventions with the Ministry of Health to address these deficiencies and selected indicators to monitor the interventions. Applying this HR TOC model enabled a systematic process to identify gaps, develop and prioritize interventions, and select indicators. Practitioners designing and evaluating SC workforce interventions should consider applying this methodology to design more effective, theory-driven interventions to improve SC workforce performance.