A more complete description is offered in "Changing The Way You Work: The Alexander Technique":

"The Alexander Technique is a method that works to change (movement) habits in our everyday activities. It is a simple and practical method for improving ease and freedom of movement, balance, support and coordination. The technique teaches the use of the appropriate amount of effort for a particular activity, giving you more energy for all your activities. It is not a series of treatments or exercises, but rather a reeducation of the mind and body. The Alexander Technique is a method which helps a person discover a new balance in the body by releasing unnecessary tension. It can be applied to sitting, lying down, standing, walking, lifting, and other daily activities..."

[Source: www.alexandertechnique.com/at.htm ]

Here are some more definitions...

The Alexander Technique:

1. is a specific method of adjusting and correcting habitual misaligned body posture in order to relieve muscle tension and allow the body to move with greater ease and efficiency.

2. is a method of mind/body integration, which leads to ease of movement and awareness.

3. is a technique concerned with improving posture to reduce or prevent arthritis.

4. is a technique that helps improve posture in movement and how to use muscles efficiently with the minimum effort to promote physical health and psychological well being.

5. is a way of learning how you can get rid of harmful tension in your body.

6. is a method that works to change (movement) habits in our everyday activities.

7. is a simple and practical method for improving ease and freedom of movement, balance, support and coordination.

8. is a method which helps a person discover a new balance in the body by releasing unnecessary tension.

9. is an intelligent way to solve body problems.

10. is a simple and practical method for self-improvement and self-help.

11. is a technique that teaches practical self-management through a constructive control of habit and reaction.

12. is a means of improving that use wherein people can further their own personal skills and activities.

13. is a method that people of all ages and abilities can learn to relieve the pain and stress caused by everyday misuse of the body.

14. is a technique that teaches how to recognize and overcome habituated limitations within a person's manner of movement and thinking.

15.  is a simple and practical method to improve poise, vitality and coordination

16. is a means of eliminating unnecessary tension while learning to move in an easier more effective way.

17. is a 100 year-old method for helping you learn how to use your body properly.

18.  is a simple and practical way for improving ease and freedom of movement and for releasing harmful tension in your body.

19. is a simple and practical way to improve your health and enhance your performance.

20. is a way of moving better and feeling better through improved co-ordination.

Sources:

www.tricesportsmedicine.com
www.alexandertechnique.com
www.stat.org.uk
www.alexandertechnique.com.au
www.ati-net.com
www.alexandertech.com
en.wikipedia.org/wiki/Alexander_technique
www.alexandertechnique.org.nz
www.alexanderschool.edu.au/alextech.htm
www.freeyourneck.com
stresseducation.com
www.alexandertechniqueatlantic.ca
www.movebetter.com.au