Kumiko is a delicate and sophisticated technique of assembling wooden pieces without the use of nails. Thinly slit wooden pieces are grooved, punched and mortised, and then fitted individually using a plane, saw, chisel and other tools to make fine adjustments. The material is made using coniferous wood, including Canadian Cedar, Japanese Cypress, Japanese Cedar, Kiso Cypress, Akita Cedar and Jindei Cedar. More than 100 different patterns are available.

The technique was developed in Japan in the Asuka Era (600-700 AD), and has since been refined and passed down through generations of craftsmen who are passionate about the tradition of Kumiko.

The Kumiko technique, which requires professional skill, is mostly used in dividers and sliding doors. But with changing lifestyles, the trend to have fewer or no Japanese-style rooms in the house, means that the number of young artisans drawn to the craft, is decreasing. Tanihata has been producing Kumiko woodwork since its foundation in 1959, promoting Kumiko, not only for traditional items, but also for modern products, thereby bridging the cultures of East and West.