This theoretical paper traces Ikujiro Nonaka’s managerial writings over a period of 25 years from 1984 to 2009. It is generally acknowledged by the academics that it was Ikujiro Nonaka who pioneered the field of Knowledge Management (KM). This paper highlights how gradual and slow was this process of developing a new field. Many academics and corporate managers have exposure of working in many cultures but rarely do their thoughts penetrate the cultural and contextual equation of the work. Nonaka however from the very outset focused on cultural and philosophical differences between American and Japanese ways of work especially in the context of managing and organizing. It was during this long discourse of over two decades that he developed many key concepts like SECI, hypertext design, rugby style management, and middle-up-down approach to management. Over the years these key concepts emerged as backbone of the KM field which surfaced formally somewhere in the mid-1990s. This paper traces the thought progression of Nonaka over a period of 20 years through his original writings published in various journals.