This paper presents one line of sociocultural psychology aiming at a better understanding of people’s development in their courses of life, unfolding in changing social and cultural environment. Adopting such a position leads me to three core questions: First, if development occurs at the junction of the social and the psychological, how can we theoretically account for the guidance of the sociocultural world upon people’s learning and development, and people’s unique capacities to create and transform these environments? Second, if one adopts such perspective, how do we account for what it that people develop through life, as they move through a plurality of situations? And third, as people learn and develop through life, how can we account for what is unique and personal?
To address these questions, I first situate the epistemological assumptions of sociocultural psychology in relation to the works of Piaget and Vygotsky. Second, I present the principles of a sociocultural psychology, and indicate the methodological strategies that I have adopted, together with a large group of colleagues over the years. The main part of the paper constitutes in responding to the three questions I raised. Finally, I propose a tentative synthesis.