In the form of foundational material required to understand decolonial thinking, this article is organized in four parts. The first section discusses the connections between decolonial thinking and other social movements; decolonial thinkers build on the insights of previous discourses and social movements, even while further developing them. The second section shows how decolonial thinking includes a radical theoretical reframing of our understanding of modernity, its emergence, and its connection to the Western European colonial project. For decolonial thinkers, modernity is predicated on domination and colonization and cannot be understood unless viewed from the perspective of its underside. The third section demonstrates that the adoption of a decolonial theoretical frame means an epistemological reconfiguration and challenging of Western European and Anglo North Atlantic forms of knowledge as the most developed expression of human "advance." Instead, they engage in the act of reclaiming the forms of knowledge of the other peoples and cultures of the world. The fourth section suggests the Latina/o theological notion of mestizaje as a concrete example of how in different contexts decolonizing impetuses are emerging. Crucial here is the emphasis that while the use of mestizaje in theology resonates with decolonizing impetuses, it predates its theoretical articulation.