Reviews the book, Participation and the Mystery: Transpersonal Essays in Psychology, Education, and Religion by Jorge N. Ferrer (2017). Participation and the Mystery offers a scholarly yet highly readable critique of transpersonal psychology’s epistemological and philosophical tendencies and biases, conscious and unconscious, and also sacrifices some of its sacred cows– gently but surely. It is impeccable in this regard. Ferrer’s attempt to create a more open approach to transpersonal theory, methodology, and practice is also welcome and needed. His examples of what this might look like in a classroom, in the field, and in a workshop should prove of real interest to educators, researchers, and therapists alike. However, despite a finely argued position to the contrary, I remain convinced that some interpretive philosophical perspective and a metaphysical foundation are not only helpful, but also necessary, to fully and coherently think through the key issues being explored in this book, as well as for formulating the kind of vision for the future that humanity so badly needs. Whether such a philosophical foundation might become a full-fledged part of transpersonal psychology, or function more in a metapsychological role, I will leave the reader to ponder. (PsycINFO Database Record (c) 2019 APA, all rights reserved)