In Japan, traditional wooden furniture is assembled without using a single nail. Advanced sashimono joinery techniques have been passed down for centuries. There are around 30 different basic types of joint. Tenons and mortises are carved to precisely matching shapes. Sashimono techniques are used not just to connect pieces of wood, but also to enhance visual impact. Master craftsmen use subtle optical illusions to make finished items look more elegant. On this edition of BEGIN Japanology, we look at sashimono woodwork, which embodies the essence of Japanese aesthetics and traditional craftsmanship.