Many factors influence the performance at the workplace. The immediate interface between the user and the equipment is, perhaps, the most important. Hence, the arrangements of the seat and work point are critical. Factors which cause discomfort and injury to seated workers are described and, from the behaviour of the spine under load, a better seat design is presented. Its use by a wide variety of workers makes it necessary to introduce increased adjustability, beyond that normally part of conventional seat design. The application of the new design in two cases in industry, as well as its introduction in schools, is briefly covered.