This book presents rich source material; it makes no claim to being academic, though referring whenever possible to works available to the authors (the bibliography more or less stops with Ian Gordon-Brown's death in 1996). However, those interested in Transpersonal Psychology as an academic discipline will be able to avail themselves of the wealth of original material here and take it into the world of comparative study. Its origins could be traced back way beyond Jung, Frankl, Maslow and Assagioli to Far Eastern and Aboriginal sources, to Greek and later Western teaching, to other great transpersonal pioneers of the twentieth century and forward into the twenty-first.