L. S. Vygotsky, the psychologist and teacher from Byelorussia who became a central figure in Soviet psychological and educational circles in the 1920s and 1930s, has become a frequent citation in 21st-century scholarship. He is most-often invoked to support some form of instructional scaffolding, based on his idea of the zone of proximal development, which is actually a relatively minor contribution in his original work. In this essay, Smagorinsky reviews how Vygotsky's theory can more broadly inform our modern-day teaching, and he attends to Vygotsky's work in the areas of the use of speech as a tool for thinking, the role of emotion in thinking, the social nature of thinking, an emphasis on meaningful activity, and how the construct of the zone of proximal development can contribute to effective language arts instruction.