Fernando González Rey (1949–2019) developed a Theory of Subjectivity from a cultural–historical approach as one of the most original contributions of Latin-American psychology to global theoretical thought. Grounded in the cultural–historical tradition, this theory conceptualizes subjectivity as a symbolic–emotional system that integrates dynamic and open individual and social dimensions. At the epistemological level, his Qualitative Epistemology and Constructive–Interpretive Methodology redefine scientific knowledge as a dialogical, creative, and nonrepresentational process that values singularity, emotion, and imagination. Developed through decades of work in Cuba and Brazil, this framework articulates ontology, theory, epistemology, and methodology into a coherent system for understanding the complex, generative, and historical character of human psychological processes. The Theory of Subjectivity has been fruitfully developed in clinical psychology, health, psychotherapy, education, and social and community psychology, offering a nonreductionist understanding of human functioning within culture.