This chapter examines the legal and normative foundations of the non-refoulement principle and its application to the Rohingya refugee crisis in Bangladesh. It evaluates the extent to which Bangladesh, despite not being a party to the 1951 Refugee Convention, remains bound by international refugee and customary international law obligations. This chapter positions non-refoulement as a cornerstone of international refugee protection, tracing its evolution through treaty law, customary norms, and human rights jurisprudence. It critically assesses Bangladesh’s domestic and international responsibilities in light of its prolonged hosting of Rohingya refugees and its repatriation policies. Particular attention is given to the legal status of non-refoulement as a peremptory norm, the relevance of international human rights instruments, and the role of international institutions, such as the UNHCR. This chapter further explores the tension between state sovereignty and international protection obligations, highlighting how restrictive refugee policies exacerbate humanitarian and environmental challenges in host communities. By analysing judicial decisions, state practice, and scholarly debates, this chapter argues that Bangladesh remains legally bound to uphold non-refoulement, irrespective of its non-signatory status to the Refugee Convention. This analysis provides a foundation for understanding the broader implications of refugee protection, environmental sustainability, and international responsibilities.