Ayahuasca is the classic hallucinogenic drug used during tribal ceremonies and ritual healing sessions in the upper Amazon area. After short analysis of possible historical antecedents to contemporary Ayahuasca use, the article treats the structure of the tribal-specific shamanic cosmology as actualized the visionary state, the culturally defined visual patterns, the specific stages of the hallucinatory perception, the symbolic integration of elements of cultural change, and the role of singing in the evocation of visions. In order to determine the healing dimensions of the rituals these structural elements are translated into concepts of depth-, transpersonal-, and parapsychology. The Ayahuasca ritual is presented as a highly efficient kind of group therapy that strengthens group cohesion and the cultural identity of the group members. However, other dimensions of parapsychological processes that require further research are also involved. (South America, Peru, ritual healing, Ayahuasca, ethnopsychology)