I remember many years ago having a solid oak swivel chair. It looked like it came out of the office of Atticus Finch. It was completely uncomfortable, harder than a rock and with its four leg base extremely prone to tipping over with me inside at a moment’s notice. Office chairs have certainly changed since the prevalent use of those old oak models. To begin with they weigh only a fraction as much, this being due to use of construction materials such as durable light weight plastics, foam for seating and fabrics. Aside from innovation in construction materials the other major development in office chairs over the years is the use of ergonomic design elements.