This paper treats how carpenters in the Middle Ages inherited and accumulated their techniques. First, an investigation revealed carpenters who come from advanced countries to bring new various techniques. Another investigation then the foreign technology was inherited by local carpenters, and they were able to build by themselves. Finally, still another investigation of an unknown craftsmen acquired high skills and productivity, and social standing improved. Consequently, the transition of carpentering could be understood by organizing it into three periods.
