This chapter explores the Indigenous moral-philosophical conceptualization of Buen Vivir (Vivir Bien/ Sumak Kawsay/Suma Qamaña) as a decolonial framework for social justice and ecological harmony, rooted in Indigenous epistemologies from the Andes and Amazon. It emphasizes the term Tinkuy, representing encounters and confrontations among diverse knowledge systems, which underscores Indigenous resistance against colonial legacies. The authors analyze the constitutional recognition of Indigenous rights in Ecuador and Bolivia, positioning Buen Vivir as a response to capitalist development models. The chapter argues for a multidimensional understanding of Buen Vivir, integrating class/justice, culture/ethnicity/ontology/epistemology, and ecologism to address the complexities of Indigenous struggles. Through comparative analysis of Indigenous and non-Indigenous perspectives, the authors highlight the importance of ethnographic research in capturing diverse voices. The political implications of Buen Vivir are examined, revealing tensions between Indigenous movements and state policies, particularly regarding extractivism. The authors advocate for recognizing the duality of particularistic and universalistic goals within Indigenous movements, framing Buen Vivir as a floating and plural conceptualization, a "flying river" that adapts to local contexts while promoting social justice. Ultimately, the chapter calls for a holistic understanding of Buen Vivir that encompasses both cultural preservation and broader socio-economic justice, underscoring its relevance in contemporary struggles for ecological sustainability and equity.