L.S. Vygotsky was a teacher, writer, and thinker in the early Soviet Union who worked in the fields of psychology, “defectology” (special education), and “pedology” (the holistic study of the child). In a meteoric career that lasted little more than a decade, he was able to lay the foundations of what has become cultural–historical psychology today. By analyzing the specifically human, cultural–historical roots of higher mental functions and emphasizing the role that language plays in development, Vygotsky provided a research method that is monist, non-reductionist, and dialectical. About the Translators: Nikolai Veresov is currently an associate professor at Monash University. He has published widely on Vygotsky in many languages, including Vygotsky’s native Russian. He is the author of Undiscovered Vygotsky (1999) and the translator of Vygotsky’s “Consciousness as a Problem in the Psychology of Behaviour” (1999) and “The Role of Play in the Development of the Child” (2016). He has also translated D.B. Elkonin’s work on periodizing child development (2000).   David Kellogg is an assistant professor at Sangmyung University in Seoul, South Korea, where he teaches courses on language and linguistics. He and his former students have published more than twelve volumes of Vygotsky translations in Korea. He is the author of The Great Globe: Narrative and Dialogue in Story-telling with Halliday, Vygotsky, and Shakespeare.