In conflict-affected settings, prevalence of alcohol use disorders (AUDs) can be high. However, limited practical information exists on AUD management in low-income settings. Using a theory of change (ToC) approach, we aimed to identify pathways influencing the implementation and maintenance of a new transdiagnostic psychological intervention ("CHANGE"), targeting both psychological distress and AUDs in humanitarian settings. Three half-day workshops in Uganda engaged 41 stakeholders to develop a ToC map. ToC is a participatory program theory approach aiming to create a visual representation of how and why an intervention leads to specific outcomes. Additionally, five semi-structured interviews were conducted to explore experiences of stakeholders that participated in the ToC workshops. Two necessary pathways influencing the implementation and maintenance of CHANGE were identified: policy impact, and mental health service delivery. Barriers identified included policy gaps, limited recognition of social determinants and the need for integrated follow-up care. Interviewed participants valued ToC's participatory approach and expressed concerns about its adaptability in continuously changing contexts (e.g., humanitarian settings). Our study underscores ToC's value in delineating context-specific outcomes and identifies areas requiring further attention. It emphasizes the importance of early planning and stakeholder engagement for sustainable implementation of psychological interventions in humanitarian settings.