The increased attention to sustainability compliance of global businesses has led Sustainable Supply Chain Management (SSCM) to become of pivotal importance. Nowadays, consumers are more conscious about sustainability issues and tend to hold large companies accountable for unsustainable and unethical behaviour. Nonetheless, in today’s global and fragmented multi-tier supply chains, managing lower-tier suppliers poses critical challenges. This systematic literature review investigates how sustainability initiatives can be diffused in multi-tier supply chains. In particular, the thesis explores the role of power sources and power dynamics in cascading sustainability practices throughout a multi-tier supply chain, an area that remains under-researched in SSCM literature.