Cortright, on the other hand, has reviewed the field of transpersonal psychotherapy and the major transpersonal models of psychotherapy, including Wilber, Jung, Washburn, Grof and Ali, as well as existential, psychoanalytic, and body-centered approaches. He also presents a unifying theoretical framework for the field of transpersonal psychotherapy, and identifies the dimension of human consciousness as central to the transpersonal realm. He also addresses clinical issues related to meditation, spiritual emergency, and altered states of consciousness. According to commentators Cortright challenges the traditional view of transpersonal psychology that a working through of psychological issues is necessary for progression on the spiritual path. Instead he suggests that these two lines of development are intertwined, and that they come to the foreground with shifting emphasis.