In Chapter 16, "The Concept of Flow," Jeanne Nakamura and Mihaly Csikszentmihalyi explore the concept of flow, which is central to positive psychology. They define a good life as one characterized by complete absorption in the present moment, or "flow." The chapter delves into the flow model of optimal experience and development, explaining how flow and related constructs are measured and discussing recent research in this area. Csikszentmihalyi's early work on the creative process in the 1960s led him to investigate the phenomenon of intrinsically motivated activity, where individuals are fully engaged in an activity for its own sake. This led to the development of the flow concept, which involves engaging in activities that present challenges appropriate to one's skills and provide clear goals and immediate feedback. When in flow, individuals experience intense and focused concentration, dynamic equilibrium, and a sense of enjoyment and fulfillment. The chapter also highlights the importance of play and work settings in understanding the conditions of flow, noting that the phenomenology of flow is similar across these contexts. It concludes by identifying promising directions for future research in the field of flow.In Chapter 16, "The Concept of Flow," Jeanne Nakamura and Mihaly Csikszentmihalyi explore the concept of flow, which is central to positive psychology. They define a good life as one characterized by complete absorption in the present moment, or "flow." The chapter delves into the flow model of optimal experience and development, explaining how flow and related constructs are measured and discussing recent research in this area. Csikszentmihalyi's early work on the creative process in the 1960s led him to investigate the phenomenon of intrinsically motivated activity, where individuals are fully engaged in an activity for its own sake. This led to the development of the flow concept, which involves engaging in activities that present challenges appropriate to one's skills and provide clear goals and immediate feedback. When in flow, individuals experience intense and focused concentration, dynamic equilibrium, and a sense of enjoyment and fulfillment. The chapter also highlights the importance of play and work settings in understanding the conditions of flow, noting that the phenomenology of flow is similar across these contexts. It concludes by identifying promising directions for future research in the field of flow.