A comprehensive review is presented of the recreational and accidental ingestion of psychoactive mushrooms in Australia and New Zealand; 15 recognized species are considered from Australia and eight from New Zealand. Common epithets, potency levels, and methods of ingestion are discussed. Legal aspects involving the use of these psychoactive fungi are noted. In addition, medical and psychoactive effects of these mushrooms and treatment for psilocybian mushroom poisoning are described. Numerous case reports, with commentary, are also presented.