Originating in Asia, lesson study is gradually spreading around the globe. As evident from the papers in this issue, we have much to learn as it is implemented in a variety of cultural contexts. In this article we reflect on the goals of lesson study, the organizational supports required to sustain the practice in various contexts, and the benefits that may be derived from making more explicit the connections between lesson study and the wider field of improvement science. Both research and practice can benefit from learning from, and about, the process of importing cultural routines.