This chapter delves into Vygotsky’s sociocultural theory, emphasizing the role of social interaction, culture, and language in cognitive development and learning. Building on Piaget’s cognitive constructivism and Vygotsky’s social constructivism, the chapter explores how higher order mental functions develop through engagement with peers, caregivers, and cultural tools. Central to this theory is the Zone of Proximal Development (ZPD), which highlights the gap between a learner’s current abilities and their potential with guidance. The chapter discusses practical classroom applications, such as collaborative learning environments, mixed-ability groupings, and the use of authentic versus contrived materials. It also addresses criticisms of sociocultural theory, including its overemphasis on social interaction and challenges in addressing individual cognitive processes. The chapter concludes with recommendations for educators to balance social and individual aspects of learning, integrate technology, and design culturally responsive activities. Discussion questions and in-class activities encourage critical engagement with the theory, fostering a deeper understanding of its implications for language education and beyond.