Charles Kelley developed Radix in California during the 60's and 70's as part of the Human Potential movement. He rejected the "medical model" and rather than a therapy, called his approach "Radix Education in Feeling" and later "Radix Education in Feeling and Purpose." Based on this educational model, Radix practitioners are traditionally known as Radix Teachers and their clients, Radix Students.

This approach paid little attention to the concepts of transference and counter-transference, and emphasised self-responsibility and self-direction in the Student. It asserted that personal development entailed risk: students were invited to sign a disclaimer at the start of the work, acknowledging that becoming more alive could make aspects of their lives intolerable to them.

While most Radix practitioners - and certainly the London Radix Workshop leaders - now work with an awareness of psychodynamic concepts, and see Radix as a form of Body Psychotherapy, the spirit of the founder still presides, and autonomy, self-direction and responsibility are part of the fabric of basic assumptions that inform the culture of the workshops.