Psychedelic substances occupy a central role in medical and spiritual paradigms throughout the world. Yet, they have been criminalized in nearly every country over the course of the 20th century. Users of psychedelics face a host of legal and political barriers in spite of mounting evidence for the safety of these substances in culturally-integrated contexts. The research presented in this thesis focuses on a Canadian branch of Santo Daime, a Brazilian syncretic religion structured around the ritualized consumption of the psychedelic plant decoction called Santo Daime, known outside the religion as ayahuasca. Generating data with participant observation and in-depth interviewing, I employ critical discourse analysis and thematic analysismethodologies derived from qualitative research — to analyze models of spirituality and healing embedded in the discourse of members of Santo Daime, and frame the group’s adaptation to the Canadian cultural context within larger trends in Canadian law and drug policy. By locating Santo Daime at a controversial intersection of mental health and culture, I bring the concepts of ontology and epistemology to bear on Santo Daime members’ worlds and worldviews, and explore their construal as radically other in relation to their largely secular cultural-political surroundings.