The growing popularity of “Supply Chain Transparency” (SCT) as an idea has motivated its use as a “buzzword,” leading to a lack of terminological clarity. Terms like visibility, transparency, and traceability are used colloquially or as synonyms for one another, yet often without a proper conceptual basis. We argue that the absence of a clear understanding of SCT limits the ability of scholars and practitioners to fully understand the role played by transparency in supply chains and to study its antecedents, technologies, types, and outcomes. Therefore, transparency research is at the point where a scoping review of literature on SCT is particularly useful. Our review first provides a formal conceptualization of SCT, allowing us to identify how transparency has been understood, the building blocks of SCT, and what distinguishes SCT from other concepts. In the review, we initially identify relevant concepts underlying SCT with a view to establish a unifying and nuanced framework for SCT. Second, using that unified conceptualization as a basis, primary outcomes such as the benefits and risks of SCT are determined. Third, we systematically detect and classify future research opportunities arising from the building blocks of SCT.