A classic chair is easy on the eyes as well as the back. RELATED LINKS Take the Design IQ Test Watch Design and Decor Videos

We spend a considerable portion of our lives sitting in chairs, but few of us ever give their design or construction a second thought. The truth is that chairs are as individual as the people who sit in them, and can range from the truly inspired to the perfectly horrible. So what makes one modern chair design a classic, and another a flop?

Kip Kotzen is the retail director for Vitra, an office furniture design company in New York City. Vitra's furniture is found in successful companies and private homes around the world, and among its products are furniture designs by the famous American designers, Charles and Ray Eames. Here Kotzen discusses what it takes for a chair design to be considered a classic:

• Simplicity and elegance.
  For a chair to become a classic, say Kotzen, there must be a wide appreciation of the use of the materials, the simplicity of the design, and the elegance of the curves and angles.
  
• New forms fit the body.
  What interests Kotzen most is when a designer is not merely decorative, but is actually trying to create new forms and designs that complement the human body. A classic design balances form and function, as chairs are both pieces of art and functional objects to be sat upon.
  
• A wide variety of materials.
  There are chairs made from every material that you can possibly imagine, from wood, plastic and leather to fabrics, aluminum, and other metals. Frank Gehry's use of cardboard in 1972 is a now classic example of taking a very elemental material and using it to create seating.
  
• Look for authorized versions.
  You can always find knockoffs of popular chair designs, but if you truly appreciate quality, you'll want to look for authorized versions made by the authorized manufacturer. Manufacturers often keep making classic chairs 5, 10 or 15 years after the original production runs so that new customers can enjoy the work of some of the world's best designers.

For more information about chairs and furniture design, check out the following organizations or websites:

Vitra, www.designaddict.com
Toy Robot.com: Chairs, www.toy-robot.com/chairs
Eames Office, www.eamesoffice.com
House of Design, www.house-of-design
The Campaign for Better Seating, www.betterseating.org