Entheogens or psychedelic drugs such as lysergic acid diethylamide (LSD) and psilocybin are associated with mystical states of experience. Drug laws currently limit research, but important new work is under way at major biomedical research facilities showing that entheogens reliably occasion mystical experiences and thereby allow research into brain states during these experiences. Are drug-occasioned mystical experiences neurologically the same as more traditional mystical states? Are there phenomenological and theological differences? As this research goes forward and the public becomes more (...) widely aware of its achievements, religious scholars and experts in science and religion will be called upon to interpret the philosophical and theological presuppositions that underpin this research and the significance of the findings that flow from it. (shrink)