In L’usage de soi, F. Matthias Alexander explains the principles of the Alexander Technique and the challenges of his long research. The Alexander Technique is an educational approach to making better use of oneself as a physical and mental entity. Using practical examples, F. Matthias Alexander illustrates the steps involved in becoming aware of and relearning psycho-physical coordination, whether this involves standing up, sitting down, walking, using the voice or playing an instrument.