Claudio Naranjo presents the nine fundamental personality structures of the Enneagram and connects them with psychoanalytic and psychodynamic theories from Freud, Fromm, Horney, Jung, Reich, and others, as well as the clinical-psychiatric personality diagnostics of the DSM (Diagnostic and Statistical Manual of Mental Disorders). The author develops a comprehensive theory of human suffering while also outlining a path of self-discovery that holds the promise of liberation and transformation. This book is the revised and updated edition of Claudio Naranjo's standard work on the psychology of the Enneatypes.