In order to survive and maintain competitive advantages in a specific market, an enterprise needs to continuously improve the level of its products' quality by using appropriate technologies, systematically increase productivity and shorten lead time. Kaizen is a significant and recognized management philosophy that can help enterprises achieve these goals, no matter what their products are. Since the concept of Kaizen was definitively put forward by Imai Masaki in 1986, Kaizen management has expanded from quality, productivity and lead time to general business, from manufacturing industries to other industries and from Japan to other countries around the world. This research note reviews the definition and method of Kaizen as the basis of Kaizen study, followed by implementation and international transfer of Kaizen in the practical domain of Kaizen study and finally extends the conceptual foundation of Kaizen into innovation study, explains the relationship between Kaizen and innovation in order not only to review and discover what have we learned about Kaizen over the past 30 years but also to strengthen the conceptual foundation and broaden the research framework of Kaizen in a clear and logical way. The ideas and findings reviewed in this research note also indicate the current state of the research stream, its overall trajectory and the emerging tendency for further research on Kaizen management and industry study in the future.