The topic of knowledge and consciousness is multidisciplinary. In the human sciences, it has been studied by various scientific and intellectual communities. The sciences of philosophy, sociology, psychology, biology, and language and communication have offered (sometimes independently of each other) numerous perspectives on this wide topic while sharing many similarities. Constructivism can be considered as an umbrella term that includes a number of subject-centered theories that give a precise, paradigmatically-shaped answer to the question about the functions of knowledge and consciousness, and their perception of their world. From the constructivist perspective, subjective instrumentarium of knowledge and consciousness helps individuals in both their construction and cognitive and practical exploration of natural and social universes (or "multiple worlds of experience"). In this study, an attempt is made to analyze the theoretical prerequisites and the genesis of constructivism as a specific multidisciplinary approach in the social sciences and the humanities. This approach conceptualizes the idea that individual and/or collective consciousness plays an active role in the formation of the everyday and scientific pictures of the world shaping the actions of social actors. Successive and distinctive features of certain constructivist concepts are presented as well as the degree of their ideological relationships, and the isomorphism and potential convertibility is revealed. Particular attention is paid to the constructivist motives of a number of popular philosophic and scientific theories of the 20th century, including neo-Kantianism; conventionalism in the philosophy and methodology of science; N. Goodman's pluralistic concept of "worldmaking" H. Maturana and F. Varela's theory of autopoiesis, in which a system is capable of reproducing and maintaining itself; cognitive psychology including G. Kelly's personal construct theory; and J. Bruner's categorization theory. © Centre for Fundamental Sociology, 2018.