Ergonomics is defined as "designing or arranging workplaces, products and systems so that they fit the people who use them". In order to be the best ergonomic chair, a chair has to fit everyone. and allow a healthy and safe sedentary lifestyle. The Sydney is the definitive embodiment of the office chair with its three-lever action and moulded seat cushion as well as its back ratchet and back height adjustment. Those flexibilities complete the definition of ergonomic chair.