This mixed-methods study critically examines the role and impact of the Intergovernmental Authority on Development (IGAD) Security Sector Programme (ISSP) in Mali, a non-member state within the IGAD region. It analyses the programme's mandate and operational framework, juxtaposing its stated objectives against the complex realities of implementation in the Malian context. Quantitative data on programme activities and resource allocation is integrated with qualitative insights from key informant interviews and document analysis to assess the perceived effectiveness and challenges of the ISSP's engagement. The findings reveal a significant gap between the programme's regional security governance aspirations and its practical influence, constrained by Mali's non-membership status, shifting domestic political dynamics, and coordination challenges with other international actors. The study concludes that while the ISSP provides a normative framework, its operational effectiveness in Mali is limited, offering critical lessons for regional security interventions in non-member states.