Triadic literature in sustainable supply chain management: paving the way

The current global scenario is characterized by complex challenges, including urgent environmental and social issues. Addressing these "grand challenges" requires the adoption of a broad perspective: supply chains are formed by multiple entities that, operating across diverse economic, social, and environmental systems, form an intricate network with wide impacts. Thus, to investigate the potential of their interactions on tackling such issues determines the need for a multi-tier approach, leveraging the interconnectedness of actors within the supply chain. Driven by mounting environmental concerns and stakeholders' pressures, sustainable supply chain management (SSCM) has received great attention. However, while previous SSCM research predominantly focuses on a single organization or, at most, on its dyadic relationships with first-tier suppliers, it is increasingly evident that sustainability efforts must extend further in the supply chain to yield significant impacts. The triadic approach, which allows to grasp a multi-tier perspective and to achieve insights on supply chain or even network phenomena, can provide an extended and nuanced understanding of SSCM, acknowledging its inherent complexity and multi-tier nature. Despite its potential, triadic and multi-tier research in SSCM remains scarce, suggesting a need for further adoption and exploration. This study conducts a systematic literature review of triadic research to inform of the state-of-the-art, encouraging further studies that can grasp the complexity of supply chain interactions and dependencies on performance – and specifically on sustainable performance.