Fifty-two North American and European participants in syncretic Brazilian church religious ceremonies were assessed for indications of personality and clinical disorders, and tendencies towards chemical dependency and addiction. Research participants attended at least 6 syncretic ceremonies and consumed a psychoactive tea, Daime, which is made from 2 Amazon Basin rainforest plants, the rainha and jagube. The research sample completed the Clinical Analysis Questionnaire (CAQ), a standardized assessment designed to reveal tendencies toward clinical and personality disorders and chemical dependence. Subgroups of the research sample (based upon age, gender, length of time associated with the Santo Daime Church, number of Festivals attended, average number of ceremonies per Festival, and preexisting diagnoses for clinical disorders) also were assessed. The norm population scores initially were compared to the research sample scores, and then compared to sample subgroup scores for each subgroup. Statistical analyses of the assessment scales scores were performed using t tests and ANOVA. Statistical analyses generally revealed no tendencies toward psychopathology or chemical dependence within the research sample. This study reveals the benefits of ethological analyses of psychoactive substance use.