Orlando Fals Borda (1925–2008) integrated a Presbyterian vocation, academic rigor, and social militancy. After studying literature and rural sociology in the United States, he became the first Colombian to earn a PhD in sociology (1955) and cofounded the Faculty of Sociology at the National University of Colombia (1961). While in Geneva (1969–1971), he helped found La Rosca, a collective that, starting in 1973, promoted Investigación-Acción Participativa (IAP) with peasant communities, achieving international visibility following the 1977 Cartagena Congress. This text reconstructs his academic, theoretical contributions and the relevance of his proposals through a chronological and relational lens. It analyzes the confluences between Fals Borda’s thought and community social psychology across epistemological, ontological, methodological, and ethical dimensions, arguing that his ideas remain a living, situated practice capable of addressing today’s psychosocial intervention challenges. Finally, it analyzes his legacy, advocating a critical, context-sensitive appropriation of his contributions within psychology today.