Abstract: A sitting device for freely chosen or fixedly attached mounting on a floor and on a subframe, or for attachment to vertical surfaces, said device comprising an array of supporting faces consisting of at least two such faces, neighboring supporting faces having different positions. One of the two neighboring supporting faces may serve to support the posterior of the occupant and the other to support the calf. Alternatively one serves to support the back and the other to support the posterior. The supporting faces comprise a forwardly inclined seat cushion and a calf cushion forming a mutual angle of at least 90.degree.. The supporting faces may be arranged at a distance from each other and with free space between these. They may be mechanically linked with each other. A set of two posterior supports, a common calf support and a common table is provided.