This document summarizes the evolution of knowledge creation theory presented by Chen Dezhao. It discusses how the theory originated from studies of Japanese companies and their emphasis on the role of middle managers. It then explains Nonaka's SECI model of knowledge conversion between tacit and explicit knowledge, and the concepts of knowledge spiral and "ba" or shared context. It traces how the theory has expanded to emphasize the role of top executives and a strategic approach. Questions are raised about applying the theory in different organizational contexts.