Achieving the Sustainable Development Goals (SDGs) requires addressing highly interlinked and complex challenges. Novel transdisciplinary collaborations between researchers and different societal actors are essential so that research is needs-based, actionable, and contributes to sustainable system transformation. Transdisciplinary research (TDR) is a concept increasingly used by researchers, funders and policymakers. However, despite its key role for reaching the SDGs, little is known about how TDR is practiced in the Global South. Moreover, many projects claim to be transdisciplinary, but do they genuinely include the voices of society, and the marginalized in particular? To address these issues, this project will answer the following questions: How can we genuinely work transdisciplinary within the context of sustainable development in the global south? And what lessons can be learned to improve transdisciplinary practice in the Global South? Through a literature review of how TDR is conceptualized and used to address SDGs in Sub-Saharan Africa, a comparative case study analysis of transdisciplinary SDG-related projects, expert workshops and reflexive learning with a cohort of PhD candidates focused on SDGs in Sub-Saharan Africa, we will co-create empirically informed lessons that enable reflexive learning within route 23, policy recommendations and collaborations to improve future TDR in SDG related initiatives.