Psychedelic or consciousness-expanding drugs have been studied by Western scientific researchers as adjuncts to psychotherapy while their plant-based equivalents are used in traditional ceremonial context for healing and spiritual practice. Plant extracts from tobacco, coca, coffee and cannabis, used as sacraments in indigenous cultures have become recreational drugs in contemporary society. Research with consciousness-expanding or entheogenic substances such as MDMA, LSD and psilocybin has focused on their value as adjuncts to psychotherapy. The worldwide underground culture has adopted the use of hallucinogenic plants and fungi, such as psilocybe mushrooms, ayahuasca, iboga and peyote, in small group hybrid therapeutic-shamanic ceremonies as well as large scale events such as raves. Core elements of such hybrid rituals are: the structure of a circle, a ritual space and altar of some kind, the presence of an experienced elder or guide, the use of eye-shades or semi-darkness and the cultivation of a respectful, spiritual attitude. Keywords: Entheogens, psychedelics, hallucinogens, consciousness expansion, MDMA, psilocybe mushrooms, ayahuasca, LSD, hybrid rituals, shamanism