This paper discusses the relationship between Lev Vygotsky's zone of proximal development and cooperative learning. Vygotsky (1896-1934), a Russian psychologist, formulated a theory that children first develop lower mental functions such as simple perceptions, associative learning, and involuntary attention; then, through social interactions with more advanced peers and adults, they eventually develop high mental functions such as language, counting, problem solving skills, voluntary attention, and memory schemas. Central to Vygotsky's theory of cognitive development is his theoretical construct of the zone of proximal development. He proposed that a child's immediate potential for cognitive growth is bounded on the lower end by what the child can accomplish on his/her own and on the upper end by what the child can accomplish with the help of a more knowledgeable other, such as a peer or teacher. This region of immediate potential is the zone of proximal development. As a child learns to complete tasks with less and less assistance, the child's cognitive skills develop. Vygotsky's ideas concerning the zone of proximal development provide strong support for the inclusion of cooperative learning strategies in classroom instruction. The five components of cooperative learning (positive interdependence, face-to-face interaction, individual accountability, small groups and interpersonal skills, and group self-evaluation) are discussed in the context of Vygotsky's theories, and a series of suggestions for using cooperative learning are included. The paper concludes that cooperative learning is an effective formal education strategy for presenting social and cultural experiences in a systematic manner. (Contains 19 references.) (ND)