Karuizawa is a popular recreational resort north-west of Tokyo. The clients wanted a quiet retreat where they could receive friends and also hold exhibitions. At the centre of the hexagonal house is a Y-shaped main space with a fully glazed window front at the end of each leg, from where there are views of the forested surrounding hills. The space itself is finished with uniformly white walls and ceilings, and a screeded floor. Mirror walls and partitions in transparent and translucent glass create constantly changing perspectives. As in traditional Japanese houses, certain functions are performed on the floor. In the kitchen, one descends a few steps into a pit to work, and the bathtub is recessed in the floor.